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10,500 | Six-Year Clinical Outcomes After Catheter Ablation of Atrial Fibrillation in Patients With Impaired Left Ventricular Function. | Long-term data after pulmonary vein isolation (PVI) in patients with impaired systolic left ventricular ejection fraction (LVEF) are sparse. This study assessed the outcomes in patients with atrial fibrillation (AF) and reduced LVEF treated with PVI after a median follow-up period of 6 years.</AbstractText>Eighty-one patients with an LVEF≤45% were evaluated; however, 1 patient was lost to follow-up. In the remaining 80 patients (male: n = 68 (85%), median age 61.6 (54.8-67.5) years) with paroxysmal (n = 16, 20%), persistent (n = 37, 46.2%), and longstanding-persistent AF (LS-AF), catheter ablation of AF using radiofrequency and 3D mapping was performed. Follow-up included Holter monitoring or pacemaker/ICD interrogation to assess for arrhythmia recurrence and echocardiography to assess LVEF. Median follow-up was 72 (67-75) months. Death occurred in 21 patients. Single-procedure success rate was 35.1% and multiple-procedure success rate was 56.8% in the overall group. Baseline median LVEF (35% [28.5-40%]) significantly increased at 6-year follow-up (56.5% [40.0-60.0%], P < 0.01). In patients with single- or multiple-procedure ablation success, there was a higher improvement of LVEF (single procedure: 25% [15.0-35] vs. 10.0% [-1.0-20.0], P < 0.01; multiple procedures: 20.0% [15-34] vs. 5.0% [5.00-15.0]; P < 0.01). The single (43.8% vs. 40%, P = 0.96) and multiple procedure success rates (62.5% vs. 60%, P = 0.47) were comparable between patients with PAF and persistent AF and lowest in patients with LS-AF (single procedure success: 23.1%, multiple-procedure success: 47.8%).</AbstractText>Single-procedure success rates after PVI during 6 years of follow-up were low. In patients with single- or multiple-procedure ablation success, a higher improvement of LVEF was observed.</AbstractText>© 2015 Wiley Periodicals, Inc.</CopyrightInformation> |
10,501 | Early post-operative ventricular arrhythmias in patients with continuous-flow left ventricular assist devices. | Ventricular arrhythmias (VAs) are common in patients with a continuous-flow left ventricular assist device (CF-LVAD). The causes and clinical significance of early post-operative VAs have not previously been characterized in these patients. The purpose of this study was to assess the incidence, precipitants, and clinical impact of early VAs in patients supported by CF-LVADs.</AbstractText>Patients with a long-term CF-LVAD receiving care between January 1, 2012, and March 1, 2014, were enrolled and followed prospectively. Implantable cardioverter-defibrillators (ICDs) were interrogated at baseline and throughout the follow-up period. VA was defined as ventricular tachycardia or ventricular fibrillation lasting >30 seconds or effectively terminated by appropriate ICD tachytherapy or external defibrillation. The primary end-point was the occurrence of early VAs (within 30 days of surgery). Secondary end-points were right ventricular (RV) failure and need for VA ablation.</AbstractText>There were 162 patients enrolled, and 38 (23.5%) experienced at least 1 early VA. Predictors of early VA were a history of pre-operative VAs, non-ischemic cardiomyopathy, and older age. Several conditions frequently encountered in the early post-operative period were identified as possible precipitants for VA episodes. Early VAs were associated with post-operative RV failure, particularly when patients received shocks instead of anti-tachycardia pacing.</AbstractText>Early VAs are common and are associated with RV failure. ICD shocks, but not anti-tachycardia pacing, for early VAs are associated with acute worsening of RV failure.</AbstractText>Copyright © 2015 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
10,502 | Transmural APD gradient synchronizes repolarization in the human left ventricular wall. | The duration and morphology of the T wave predict risk for ventricular fibrillation. A transmural gradient in action potential duration (APD) in the ventricular wall has been suggested to underlie the T wave in humans. We hypothesize that the transmural gradient in APD compensates for the normal endocardium-to-epicardium activation sequence and synchronizes repolarization in the human ventricular wall.</AbstractText>We made left ventricular wedge preparations from 10 human donor hearts and measured transmural activation and repolarization patterns by optical mapping, while simultaneously recording a pseudo-ECG. We also studied the relation between local timings of repolarization with the T wave in silico. During endocardial pacing (1 Hz), APD was longer at the subendocardium than at the subepicardium (360 ± 17 vs. 317 ± 20 ms, P < 0.05). The transmural activation time was 32 ± 4 ms and resulted in final repolarization of the subepicardium at 349 ± 18 ms. The overall transmural dispersion in repolarization time was smaller than that of APD. During epicardial pacing, the dispersion in repolarization time increased, whereas that of APD remained similar. The morphology of the T wave did not differ between endocardial and epicardial stimulation. Simulations explained the constant T wave morphology without transmural APD gradients.</AbstractText>The intrinsic transmural difference in APD compensates for the normal cardiac activation sequence, resulting in more homogeneous repolarization of the left ventricular wall. Our data suggest that the transmural repolarization differences do not fully explain the genesis of the T wave.</AbstractText>Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.</CopyrightInformation> |
10,503 | Post-transcriptional regulation of cardiac sodium channel gene SCN5A expression and function by miR-192-5p. | The SCN5A gene encodes cardiac sodium channel Nav1.5 and causes lethal ventricular arrhythmias/sudden death and atrial fibrillation (AF) when mutated. MicroRNAs (miRNAs) are important post-transcriptional regulators of gene expression, and involved in the pathogenesis of many diseases. However, little is known about the regulation of SCN5A by miRNAs. Here we reveal a novel post-transcriptional regulatory mechanism for expression and function of SCN5A/Nav1.5 via miR-192-5p. Bioinformatic analysis revealed that the 3'-UTR of human and rhesus SCN5A, but not elephant, pig, rabbit, mouse, and rat SCN5A, contained a target binding site for miR-192-5p and dual luciferase reporter assays showed that the site was critical for down-regulation of human SCN5A. With Western blot assays and electrophysiological studies, we demonstrated that miR-192-5p significantly reduced expression of SCN5A and Nav1.5 as well as peak sodium current density INa generated by Nav1.5. Notably, in situ hybridization, immunohistochemistry and real-time qPCR analyses showed that miR-192-5p was up-regulated in tissue samples from AF patients, which was associated with down-regulation of SCN5A/Nav1.5. These results demonstrate an important post-transcriptional role of miR-192-5p in post-transcriptional regulation of Nav1.5, reveal a novel role of miR-192-5p in cardiac physiology and disease, and provide a new target for novel miRNA-based antiarrhythmic therapy for diseases with reduced INa. |
10,504 | ICD Shock, Not Ventricular Fibrillation, Causes Elevation of High Sensitive Troponin T after Defibrillation Threshold Testing--The Prospective, Randomized, Multicentre TropShock-Trial. | The placement of an implantable cardioverter defibrillator (ICD) has become routine practice to protect high risk patients from sudden cardiac death. However, implantation-related myocardial micro-damage and its relation to different implantation strategies are poorly characterized.</AbstractText>A total of 194 ICD recipients (64±12 years, 83% male, 95% primary prevention of sudden cardiac death, 35% cardiac resynchronization therapy) were randomly assigned to one of three implantation strategies: (1) ICD implantation without any defibrillation threshold (DFT) testing, (2) estimation of the DFT without arrhythmia induction (modified "upper limit of vulnerability (ULV) testing") or (3) traditional safety margin testing including ventricular arrhythmia induction. High-sensitive Troponin T (hsTnT) levels were determined prior to the implantation and 6 hours after.</AbstractText>All three groups showed a postoperative increase of hsTnT. The mean delta was 0.031±0.032 ng/ml for patients without DFT testing, 0.080±0.067 ng/ml for the modified ULV-testing and 0.064±0.056 ng/ml for patients with traditional safety margin testing. Delta hsTnT was significantly larger in both of the groups with intraoperative ICD testing compared to the non-testing strategy (p≤0.001 each). There was no statistical difference in delta hsTnT between the two groups with intraoperative ICD testing (p = 0.179).</AbstractText>High-sensitive Troponin T release during ICD implantation is significantly higher in patients with intraoperative ICD testing using shock applications compared to those without testing. Shock applications, with or without arrhythmia induction, did not result in a significantly different delta hsTnT. Hence, the ICD shock itself and not ventricular fibrillation seems to cause myocardial micro-damage.</AbstractText>ClinicalTrials.gov NCT01230086.</AbstractText> |
10,505 | A Grouped Up-and-Down Method Used for Efficacy Comparison Between Two Different Defibrillation Waveforms. | Electrical defibrillation, which consists of delivering a therapeutic dose of the electrical current to the fibrillating heart with the aid of a defibrillator, is still the only effective way to treat life-threatening ventricular fibrillation (VF). However, the efficacy of electrical therapy for terminating VF is highly dependent on the waveform applied. When new defibrillation waveforms or techniques are developed, their efficacy needs to be accurately evaluated and compared to those in use. A common method for the comparison of defibrillation efficacy is to estimate and compare the individual defibrillation threshold (DFT) by constructing dose response curves or using an up-and-down method. Since DFT is calculated by repetitive and sequential shocks, there will be variability for each measurement and for each individual. This creates a considerable uncertainty for paired comparison. In this paper, a novel grouped up-and-down method is developed for the comparison of defibrillation efficacy between two different defibrillation waveforms or techniques. The efficacy of two commonly used biphasic defibrillation waveforms was compared in a porcine model of cardiac arrest using the developed method. Experimental results demonstrate that the proposed method is more sensitive for efficacy comparison and requires less defibrillation attempts compared with traditional DFT methods. |
10,506 | Very Low Ventricular Pacing Rates Can Be Achieved Safely in a Heterogeneous Pacemaker Population and Provide Clinical Benefits: The CANadian Multi-Centre Randomised Study-Spontaneous AtrioVEntricular Conduction pReservation (CAN-SAVE R) Trial. | It is well recognized that right ventricular apical pacing can have deleterious effects on ventricular function. We performed a head-to-head comparison of the SafeR pacing algorithm versus DDD pacing with a long atrioventricular delay in a heterogeneous population of patients with dual-chamber pacemakers.</AbstractText>In a multicenter prospective double-blinded randomized trial conducted at 10 centers in Canada, 373 patients, age 71±11 years, with indications for dual chamber DC pacemakers were randomized 1:1 to SafeR or DDD pacing with a long atrioventricular delay (250 ms). The primary objective was twofold: (1) reduction in the proportion of ventricular paced beats at 1 year; and (2) impact on atrial fibrillation burden at 3 years, defined as the ratio between cumulative duration of mode-switches divided by follow-up time. Statistical significance of both co-primary end points was required for the trial to be considered positive. At 1 year of follow-up, the median proportion of ventricular-paced beats was 4.0% with DDD versus 0% with SafeR (P<0.001). At 3 years of follow-up, the atrial fibrillation burden was not significantly reduced with SafeR versus DDD (median 0.00%, interquartile range [0.00% to 0.23%] versus median 0.01%, interquartile range [0.00% to 0.44%], respectively, P=0.178]), despite a persistent reduction in the median proportion of ventricular-paced beats (10% with DDD compared to 0% with SafeR).</AbstractText>A ventricular-paced rate <1% was safely achieved with SafeR in a population with a wide spectrum of indications for dual-chamber pacing. However, the lower percentage of ventricular pacing did not translate into a significant reduction in atrial fibrillation burden.</AbstractText>URL: https://www.clinicaltrials.gov/ Unique identifier: NCT01219621.</AbstractText>© 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.</CopyrightInformation> |
10,507 | Causes for the declining proportion of ventricular fibrillation in out-of-hospital cardiac arrest. | The reported proportion of ventricular fibrillation (VF) in out-of-hospital cardiac arrest (OHCA) has declined worldwide. VF decline may be caused by less VF at collapse and/or faster dissolution of VF into asystole. We aimed to determine the causes of VF decline by comparing VF proportions in relation to delay from emergency medical services (EMS) call to initial ECG (call-to-ECG delay), and VF dissolution rates between two study periods.</AbstractText>Data from the AmsteRdam REsuscitation STudies (ARREST), an ongoing OHCA registry in the Netherlands, were used. We studied cardiac OHCA in the study periods 1995-1997 (n=917) and 2006-2012 (n=5695). Cases with available ECG and information on call-to-ECG delay were included. We tested whether initial VF proportion and VF dissolution rates differed between both study periods using logistic regression.</AbstractText>Despite a 15% VF decline between the periods, VF proportion around EMS call remained high in 2006-2012 (64%). The odds ratio (OR) for VF proportion in 2006-2012 vs. 1995-1997 was 0.52 (95%-CI 0.45-0.60, P<0.001), with similar rates of VF dissolution in both periods (P=0.83). VF decline was higher for unwitnessed collapse (OR 0.41, 95%-CI 0.28-0.58) and collapse at home (OR 0.50, 95%-CI 0.42-0.59), but not for categories of bystander CPR, age or sex.</AbstractText>VF proportion early after collapse remains high. VF decline is explained by the occurrence of less initial VF, rather than faster dissolving VF. An increase in unwitnessed OHCA and collapse at home contributes to the observed VF decline.</AbstractText>Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
10,508 | The Early Repolarization Pattern: A Consensus Paper. | The term early repolarization has been in use for more than 50 years. This electrocardiographic pattern was considered benign until 2008, when it was linked to sudden cardiac arrest due to idiopathic ventricular fibrillation. Much confusion over the definition of early repolarization followed. Thus, the objective of this paper was to prepare an agreed definition to facilitate future research in this area. The different definitions of the early repolarization pattern were reviewed to delineate the electrocardiographic measures to be used when defining this pattern. An agreed definition has been established, which requires the peak of an end-QRS notch and/or the onset of an end-QRS slur as a measure, denoted Jp, to be determined when an interpretation of early repolarization is being considered. One condition for early repolarization to be present is Jp ≥0.1 mV, while ST-segment elevation is not a required criterion. |
10,509 | Good at Heart: Preserving Cardiac Metabolism during aging. | The natural process of aging determinates several cardiac modifications with increased susceptibility to heart diseases and ultimately converging on development of chronic heart failure as final stage. These changes mainly include left ventricular hypertrophy, diastolic dysfunction, valvular degeneration, increased cardiac fibrosis, increased prevalence of atrial fibrillation, and decreased maximal exercise capacity, as demonstrated in several humans and animal models of aging. While different theories have been proposed to explain the natural process of aging, it is clear that most of the alterations affect mechanisms involved in cell homeostasis and maintenance. Latest research studies have in particular focused on role of mitochondrial oxidative stress, energy production and mitochondria quality control. This article reviews the central role played by this organelle in aging and the role of new molecular players involved into the progression toward heart failure and potentially susceptible of new "anti-aging" strategies. |
10,510 | Treatment of Atrial Fibrillation. | Atrial fibrillation is a common arrhythmia that affects more than 2.5 million people in the United States and causes substantial morbidity and mortality, especially regarding the increased risk of stroke.</AbstractText>To summarize atrial fibrillation treatment exclusive of stroke prevention.</AbstractText>An Ovid MEDLINE comprehensive literature search was performed on atrial fibrillation therapy excluding anticoagulation and emphasizing studies published within the last 5 years through April 2015 (N = 5044 references). The 2014 atrial fibrillation guideline from the American Heart Association, the American College of Cardiology, and the Heart Rhythm Society also was reviewed.</AbstractText>Reversible causes of atrial fibrillation should be identified. Risk factor modification, including weight loss and treatment of hypertension, diabetes, and obstructive sleep apnea can reduce atrial fibrillation episodes. Appropriate anticoagulation is necessary for patients at substantial stroke risk regardless of rate or rhythm treatment strategy. Sinus rhythm is often needed to control symptoms; however, an alternative strategy for atrial fibrillation is appropriate rate control. Rate control is safe in older patients (those who are about age ≥65 years) followed up for a few years, but no such safety data exist for patients younger than 60 years or for those followed up for longer periods. Thus, selection of therapy is individualized, taking into account present and future medical problems for the patient. Choice of an antiarrhythmic drug is based on safety first vs efficacy. Catheter ablation is an effective nonpharmacological alternative that is often, but not always, the second-line treatment. Reduction of the frequency and duration of atrial fibrillation episodes that result in a significant improvement in quality of life is a good marker of drug treatment success and complete elimination of atrial fibrillation is not required in many patients. Rate control is usually achieved with a β-blocker or non-dihydropyridine calcium channel blockers. It is important to assess adequate rate control during both rest and activity. If the ventricular rate goes uncontrolled for a prolonged period, tachycardia-mediated cardiomyopathy can occur.</AbstractText>Therapy for atrial fibrillation includes prevention and modification of inciting causes and appropriate anticoagulation. Rate control is necessary for all patients. Maintenance of sinus rhythm with drugs or catheter ablation should be considered based on the individual needs of each patient.</AbstractText> |
10,511 | Ultrarapid Induction of Hypothermia Using Continuous Automated Peritoneal Lavage With Ice-Cold Fluids: Final Results of the Cooling for Cardiac Arrest or Acute ST-Elevation Myocardial Infarction Trial. | Hypothermia (32-34 °C) can mitigate ischemic brain injury, and some evidence suggests that it can reduce infarct size in acute myocardial infarction and acute ischemic stroke. For some indications, speed of cooling may be crucial in determining efficacy. We performed a multicenter prospective intervention study to test an ultrarapid cooling technology, the Velomedix Automated Peritoneal Lavage System using ice-cold fluids continuously circulating through the peritoneal cavity to rapidly induce and maintain hypothermia in comatose patients after cardiac arrest and a small number of awake patients with acute myocardial infarction.</AbstractText>Multicenter prospective intervention study.</AbstractText>Intensive care- and coronary care units of multiple tertiary referral centers.</AbstractText>Access to the peritoneal cavity was gained using a modified blunt dilating instrument, followed by catheter placement. Patients were cooled to a temperature of 32.5 °C, maintained for 24 hours (cardiac arrest) or 3 hours (acute myocardial infarction) followed by controlled rewarming. Forty-nine patients were enrolled, and 46 patients completed treatment. One placement was unsuccessful (abdominal wall not breached), two patients were ultimately not cooled, and only safety data are reported. Average catheter insertion time was 2.3 minutes. Mean time to temperature less than 33 °C was 10.4 minutes (average cooling rate, 14 °C/hr). Median infarct size in patients who had coronary interventions was 16% of LV. No cases of stent thrombosis occurred. Survival in cardiac arrest patients with initial rhythm of ventricular tachycardia/ventricular fibrillation was 56%, of whom 82 had a complete neurologic recovery. This compares favorably to outcomes from previous studies.</AbstractText>Automated peritoneal lavage system is a safe and ultrarapid method to induce and maintain hypothermia, which appears feasible in cardiac arrest patients and awake patients with acute myocardial infarction. The shivering response appeared to be delayed and much reduced with this technology, diminishing metabolic disorders associated with cooling and minimizing sedation requirement. Our data suggest that ultrarapid cooling could prevent subtle neurologic damage compared with slower cooling. This will need to be confirmed in direct comparative studies.</AbstractText> |
10,512 | [Arrhythmia and sleep apnea syndrome]. | Arrhythmia is a major cause of morbidity and mortality in Europe and in the United States. The aim of this review article was to assess the results of the prospective studies that evaluated the risk of arrhythmia in patients with sleep apnea syndrome and discuss the management of this arrhythmia.</AbstractText>Reports published with the following search terms were searched: sleep apnea syndrome, atrial flutter, supraventricular arrhythmia, ventricular arrhythmia, ventricular tachycardia, ventricular fibrillation, torsade de pointe, atrial fibrillation and sudden death. The investigation was restricted to reports published in English and French.</AbstractText>The outcome of this analysis suggests that patients with untreated overt sleep apnea syndrome are at increased risk of arrhythmia.</AbstractText>The timely recognition and effective treatment of sleep apnea syndrome in patients with arrhythmia are mandatory because the prognosis of arrhythmia may be improved with the appropriate treatment of sleep apnea syndrome.</AbstractText>Copyright © 2015. Published by Elsevier Masson SAS.</CopyrightInformation> |
10,513 | Survival without sequelae after prolonged cardiopulmonary resuscitation after electric shock. | "Electrical shock is the physiological reaction or injury caused by electric current passing through the human body. It occurs upon contact of a human body part with any source of electricity that causes a sufficient current through the skin, muscles, or hair causing undesirable effects ranging from simple burns to death." Ventricular fibrillation is believed to be the most common cause of death after electrical shock. "The ideal duration of cardiac resuscitation is unknown. Typically prolonged cardiopulmonary resuscitation is associated with poor neurologic outcomes and reduced long term survival. No consensus statement has been made and traditionally efforts are usually terminated after 15-30 minutes." The case under discussion seems worthy of the somewhat detailed description given. It is for a young man who survived after 65 minutes after electrical shock (ES) after prolonged high-quality cardiopulmonary resuscitation (CPR), multiple defibrillations, and artificial ventilation without any sequelae. Early start of adequate chest compressions and close adherence to advanced cardiac life support protocols played a vital role in successful CPR. |
10,514 | Relationship of quantitative parameters of myocardial perfusion SPECT and ventricular arrhythmia in patients receiving cardiac resynchronization therapy. | Ventricular arrhythmia is the major cause of sudden cardiac death for patients with heart failure, including those receiving implantation of cardiac resynchronization therapy (CRT). The purpose of this study was to assess the value of myocardial perfusion SPECT (MPS) in predicting ventricular arrhythmia for patients with CRT.</AbstractText>Fifty-one patients (35 males, mean age 64 ± 12 years) who had received CRT for at least 6 months were enrolled for resting gated MPS. Three main quantitative parameters of MPS, including extent of myocardial scar, left ventricular ejection fraction (LVEF) and LV dyssynchrony (phase SD), were generated by Emory Cardiac Toolbox. Using the recorded ventricular arrhythmia in the device, including ventricular tachycardia (VT) and ventricular fibrillation (VF), as the primary end point, the value of quantitative parameters of MPS in predicting the development of VT/VF was assessed.</AbstractText>Twenty (39 %) of the 51 patients developed VT/VF during the follow-up (15.3 ± 12.7 months). The patients with VT/VF had significantly lower LVEF (24 ± 12 vs. 36 ± 17 %, p < 0.005), larger scar areas (36 ± 19 vs. 22 ± 12 %, p < 0.05) and larger phase SD (57° ± 20° vs. 43° ± 17°, p < 0.01). When categorizing the patients by the median values of LVEF, scar and phase SD, univariate regression analysis showed that lower LVEF (<29 %), larger scar (>23 %) and larger phase SD (>50°) were related to the development of VT/VF (p = 0.006, 0.011 and 0.064, respectively). However, only LVEF was marginally significant as an independent predictor of VT//VF on multivariate regression analysis (p = 0.0573). Survival analysis with Kaplan-Meier curves showed that the survival probability for VT/VF in those with LVEF >29 %, scar areas <23 % and phase SD < 50° was significantly better than in the others (HR 5.16, 95 % CI 1.20-22.16) by log-rank test (χ (2) = 5.9894, p = 0.014).</AbstractText>Lower LVEF, larger scar and/or more dyssynchrony assessed by MPS were related to the development of ventricular arrhythmia for patients with CRT, and further defibrillator implantation may be considered for these patients.</AbstractText> |
10,515 | Carnitine deficiency induces a short QT syndrome. | Short QT syndrome is associated with an increased risk of cardiac arrhythmias and unexpected sudden death. Until now, only mutations in genes encoding the cardiac potassium and calcium channels have been implicated in early T-wave repolarization.</AbstractText>The purpose of this study was to confirm a relationship between a short QT syndrome and carnitine deficiency.</AbstractText>We report 3 patients affected by primary systemic carnitine deficiency and an associated short QT syndrome. Ventricular fibrillation during early adulthood was the initial symptom in 1 case. To confirm the relationship between carnitine, short QT syndrome, and arrhythmias, we used a mouse model of carnitine deficiency induced by long-term subcutaneous perfusion of MET88.</AbstractText>MET88-treated mice developed cardiac hypertrophy associated with a remodeling of the mitochondrial network. The continuous monitoring of electrocardiograms confirmed a shortening of the QT interval, which was negatively correlated with the plasma carnitine concentration. As in humans, such alterations coincided with the genesis of ventricular premature beats and ventricular tachycardia and fibrillation.</AbstractText>Altogether, these results suggest that long-chain fatty acid metabolism influence the morphology and the electrical function of the heart.</AbstractText>Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
10,516 | Gap junction modifier rotigaptide decreases the susceptibility to ventricular arrhythmia by enhancing conduction velocity and suppressing discordant alternans during therapeutic hypothermia in isolated rabbit hearts. | Therapeutic hypothermia (TH) may increase the susceptibility to ventricular arrhythmias by decreasing ventricular conduction velocity (CV) and facilitating arrhythmogenic spatially discordant alternans (SDA).</AbstractText>The purpose of this study was to test the hypothesis that rotigaptide, a gap junction enhancer, can increase ventricular CV, delay the onset of SDA, and decrease the susceptibility to pacing-induced ventricular fibrillation (PIVF) during TH.</AbstractText>Langendorff-perfused isolated rabbit hearts were subjected to 30-minute moderate hypothermia (33°C) followed by 20-minute treatment with rotigaptide (300 nM, n = 8) or vehicle (n = 5). The same protocol was also performed at severe hypothermia (30°C; n = 8 for rotigaptide, n = 5 for vehicle). Using an optical mapping system, epicardial CV and SDA threshold were evaluated by S1 pacing. Ventricular fibrillation inducibility was evaluated by burst pacing for 30 seconds at the shortest pacing cycle length (PCL) that achieved 1:1 ventricular capture.</AbstractText>Rotigaptide increased ventricular CV during 33°C (PCL 300 ms, from 76 ± 6 cm/s to 84 ± 7 cm/s, P = .039) and 30°C (PCL 300 ms, from 62 ± 6 cm/s to 68 ± 4 cm/s, P = .008). Rotigaptide decreased action potential duration dispersion at 33°C (P = .01) and 30°C (P = .035). During 30°C, SDA thresholds (P = .042) and incidence of premature ventricular complexes (P = .025) were decreased by rotigaptide. PIVF inducibility was decreased by rotigaptide at 33°C (P = .039) and 30°C (P = .042). Rotigaptide did not change connexin43 expressions and distributions during hypothermia.</AbstractText>Rotigaptide protects the hearts against ventricular arrhythmias by increasing ventricular CV, delaying the onset of SDA, and reducing repolarization heterogeneity during TH. Enhancing cell-to-cell coupling by rotigaptide might be a novel approach to prevent ventricular arrhythmias during TH.</AbstractText>Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
10,517 | Impact of atrial fibrillation ablation on cardiac sympathetic nervous system in patients with and without heart failure. | <AbstractText Label="BACKGROUND/OBJECTIVES" NlmCategory="OBJECTIVE">Catheter ablation of atrial fibrillation (AF) might influence the cardiac autonomic nervous system. To investigate the impact of catheter ablation on the sympathetic nervous function in AF patients with and without heart failure (HF) using cardiac iodine-123-metaiodobenzylguanidine ((123)I-mIBG) scintigraphy, and the association of this effect with AF recurrence.</AbstractText>Forty consecutive patients (median age, 65 (54-69) years; male, 29) with paroxysmal (n=22) and persistent (n=18) AF who were scheduled for ablation were enrolled. Twelve (30%) of these patients also exhibited either stable HF, defined as an ejection fraction <40%, or a history of symptomatic HF. (123)I-mIBG scintigraphy was performed at baseline and 3months post-ablation. The heart-to-mediastinum ratio of (123)I-mIBG uptake at 15min (H/M15min) and 240min (H/M240min), as well as the washout rate (WR) were measured.</AbstractText>During an 11±4-month follow-up, AF recurrence was observed in 8 (20%) patients receiving no antiarrhythmic drugs. Patients with HF had a tendency toward a lower baseline H/M15min (1.91±0.06 vs. 2.05±0.04, p=0.07), significantly lower H/M240min (1.88±0.22 vs. 2.14±0.28, p=0.008), and higher WR (40.3±9.0 vs. 32.3±7.4, p=0.007). Post-ablation, WR decreased in patients with HF (40.2±8.5 to 29.0±8.9, p=0.02) but slightly increased in those without (32.0±7.4 to 34.6±10.3, p=0.04). WR post-ablation independently predicted AF recurrence (adjusted hazard ratio=1.14 for 1 percentage point increase in the WR, 95% coincidence interval=1.02-1.34, p=0.02).</AbstractText>AF ablation restores sympathetic nervous system status via attenuation of excessive adrenergic tone in HF patients. Elevated sympathetic nervous tone 3months post-ablation was a reliable predictor of AF recurrence.</AbstractText>Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
10,518 | Sugammadex Use in a Patient with Wolff-Parkinson-White (WPW) Syndrome. | Wolff-Parkinson-White (WPW) syndrome is a disease associated with episodes of supraventricular tachycardia and ventricular pre-excitation or atrial fibrillation. WPW is characterized by an aberrant electrical conduction pathway between atria and ventricles.</AbstractText>The major anesthetic problem connected with WPW syndrome is the risk of tachyarrhythmias due to accessory pathway. Therefore, it has been proposed that the aim of anesthetic management should be the avoidance of tachyarrhythmia and sympathetic stimulation. Sugammadex was administered as a neuromuscular reversal agent in this case. To our knowledge, this is the first case report of sugammadex use in a patient with WPW. This report presents a case of general anesthesia management in a patient with WPW syndrome.</AbstractText>We think that it is appropriate to use sugammadex to reverse rocuronium for the prevention of sudden hemodynamic changes in patients with WPW who underwent general anesthesia.</AbstractText> |
10,519 | Tricuspid regurgitation following left-sided valve surgery: echocardiographic evaluation and optimal timing of surgical treatment. | Severe tricuspid regurgitation may often appear and progress late after left-sided valve surgery without left-sided valve dysfunction, significant left heart failure, and pulmonary hypertension. The clinical features, echocardiographic evaluation, treatment, and prognosis of this disease entity have been discussed, but data is limited compared with left-sided valve diseases. Tricuspid annular dilatation associated with atrial fibrillation and right ventricular dysfunction strongly relate to development of isolated tricuspid regurgitation late after left-sided valve surgery. Three-dimensional evaluation may be useful in evaluating tricuspid valve anatomy in more detail. Better prognosis in patients undergoing surgical treatment for severe isolated tricuspid regurgitation than those who were treated medically has been reported; however, the timing of isolated tricuspid valve surgery is often too late. Right ventricular function is a key word for determining the timing of isolated tricuspid valve surgery; however, it is difficult to evaluate by conventional echocardiography. One of the serious issues in the future will be how to accurately evaluate right ventricular function. |
10,520 | Frequency of Left Ventricular Hypertrophy in Non-Valvular Atrial Fibrillation. | Left ventricular hypertrophy (LVH) is significantly related to adverse clinical outcomes in patients at high risk of cardiovascular events. In patients with atrial fibrillation (AF), data on LVH, that is, prevalence and determinants, are inconsistent mainly because of different definitions and heterogeneity of study populations. We determined echocardiographic-based LVH prevalence and clinical factors independently associated with its development in a prospective cohort of patients with non-valvular (NV) AF. From the "Atrial Fibrillation Registry for Ankle-brachial Index Prevalence Assessment: Collaborative Italian Study" (ARAPACIS) population, 1,184 patients with NVAF (mean age 72 ± 11 years; 56% men) with complete data to define LVH were selected. ARAPACIS is a multicenter, observational, prospective, longitudinal on-going study designed to estimate prevalence of peripheral artery disease in patients with NVAF. We found a high prevalence of LVH (52%) in patients with NVAF. Compared to those without LVH, patients with AF with LVH were older and had a higher prevalence of hypertension, diabetes, and previous myocardial infarction (MI). A higher prevalence of ankle-brachial index ≤0.90 was seen in patients with LVH (22 vs 17%, p = 0.0392). Patients with LVH were at significantly higher thromboembolic risk, with CHA2DS2-VASc ≥2 seen in 93% of LVH and in 73% of patients without LVH (p <0.05). Women with LVH had a higher prevalence of concentric hypertrophy than men (46% vs 29%, p = 0.0003). Logistic regression analysis demonstrated that female gender (odds ratio [OR] 2.80, p <0.0001), age (OR 1.03 per year, p <0.001), hypertension (OR 2.30, p <0.001), diabetes (OR 1.62, p = 0.004), and previous MI (OR 1.96, p = 0.001) were independently associated with LVH. In conclusion, patients with NVAF have a high prevalence of LVH, which is related to female gender, older age, hypertension, and previous MI. These patients are at high thromboembolic risk and deserve a holistic approach to cardiovascular prevention. |
10,521 | Independent Assessment of the European Society of Cardiology Sudden Death Risk Model for Hypertrophic Cardiomyopathy. | Risk stratification for sudden death (SD) is an essential component of hypertrophic cardiomyopathy (HC) management, given the proven effectiveness of implantable cardioverter-defibrillators (ICD) for preventing SD. Although highly effective in identifying high-risk patients, current stratification algorithms remain incomplete and novel strategies are encouraged. In this regard, reliability of the statistical model to predict SD risk in HC, as recommended by the recent European Society of Cardiology (ESC) guidelines, was retrospectively tested in an independent cohort of 1,629 consecutive patients with HC aged ≥16 years. Of the 1,629 patients, 35 incurred SD events, but only 4 of these (11%) had high predictive risk scores >6%/5 years consistent with an ICD recommendation, and most (60%; n = 21) had scores <4%/5 years that would not justify ICDs. Of 46 high-risk patients with appropriate ICD interventions for ventricular fibrillation/tachycardia, 27 (59%) had low SD risk scores of <4%/5 years, regarded by ESC as insufficient to recommend ICDs, and only 12 (26%) had scores >6%/5 years, considered an ICD indication; 11 of these 12 had already met conventional criteria warranting implantation with 2 to 3 risk markers. Of 414 patients with ICDs but without appropriate interventions, 258 (62%) had low risk scores (<4%/5 years) that would argue against implant. In conclusion, primary risk stratification using the ESC prognostic score applied retrospectively to a large independent HC cohort proved unreliable for prediction of future SD events. Most patients with HC with SD or appropriate ICD interventions were misclassified with low risk scores and therefore would have remained unprotected from arrhythmic SD without ICDs. |
10,522 | Pharmacological treatment of acquired QT prolongation and torsades de pointes. | Torsades de pointes (TdP) is a characteristic polymorphic ventricular arrhythmia associated with delayed ventricular repolarization as evidenced on the surface electrocardiogram by QT interval prolongation. It typically occurs in self-limiting bursts, causing dizziness and syncope, but may occasionally progress to ventricular fibrillation and sudden death. Acquired long QT syndromes are mainly caused by cardiac disease, electrolyte abnormalities or exposure to drugs that block rectifying potassium channels, especially IKr. Management of TdP or marked QT prolongation includes removal or correction of precipitants, including discontinuation of culprit drugs and institution of cardiac monitoring. Electrolyte abnormalities and hypoxia should be corrected, with potassium concentrations maintained in the high normal range. Immediate treatment of TdP is by intravenous administration of magnesium sulphate, terminating prolonged episodes using electrical cardioversion. In refractory cases of recurrent TdP, the arrhythmia can be suppressed by increasing the underlying heart rate using isoproterenol (isoprenaline) or transvenous pacing. Other interventions are rarely needed, but there are case reports of successful use of lidocaine or phenytoin. Anti-arrhythmic drugs that prolong ventricular repolarization should be avoided. Some episodes of TdP could be avoided by careful prescribing of QT prolonging drugs, including an individualized assessment of risks and benefits before use, performing baseline and periodic electrocardiograms and measurement of electrolytes, especially during acute illnesses, using the lowest effective dose for the shortest possible time and avoiding potential drug interactions. These steps are particularly important in those with underlying repolarization abnormalities and those who have previously experienced drug-induced TdP. |
10,523 | Association of Admission Glycaemia With High Grade Atrioventricular Block in ST-Segment Elevation Myocardial Infarction Undergoing Reperfusion Therapy: An Observational Study. | Several studies have demonstrated the association between elevated admission glycaemia (AG) and the occurrence of some arrhythmias such as atrial fibrillation, ventricular tachycardia, and ventricular fibrillation after myocardial infarction. However, the impact of elevated AG on the high grade atrioventricular block (AVB) occurrence after ST-segment elevation myocardial infarction (STEMI) remains unclear. Included were 3359 consecutive patients with STEMI who received reperfusion therapy. The primary endpoint was the development of high grade AVB during hospital course. Patients were divided into non-diabetes mellitus (DM), newly diagnosed DM, and previously known DM according to the hemoglobin A1c level. The optimal AG value was determined by receiver operating characteristic curves analysis with AG predicting the high grade AVB occurrence. The best cut-off value of AG for predicting the high grade AVB occurrence was 10.05 mmol/L by ROC curve analysis. The prevalence of AG ≥ 10.05 mmol/L in non-DM, newly diagnosed DM, and previously known DM was 15.7%, 34.1%, and 68.5%, respectively. The incidence of high grade AVB was significantly higher in patients with AG ≥ 10.05  mmol/L than <10.05  mmol/L in non-DM (5.7% vs. 2.1%, P < 0.001) and in newly diagnosed DM (10.2% vs.1.4%, P < 0.001), but was comparable in previously known DM (3.6% vs. 0.0%, P = 0.062). After multivariate adjustment, AG ≥ 10.05  mmol/L was independently associated with increased risk of high grade AVB occurrence in non-DM (HR = 1.826, 95% CI 1.073-3.107, P = 0.027) and in newly diagnosed DM (HR = 5.252, 95% CI 1.890-14.597, P = 0.001). Moreover, both AG ≥ 10.05  mmol/L and high grade AVB were independent risk factors of 30-day all cause-mortality (HR = 1.362, 95% CI 1.006-1.844, P = 0.046 and HR = 2.122, 95% CI 1.154-3.903, P = 0.015, respectively). Our study suggested that elevated AG level (≥10.05  mmol/L) might be an indicator of increased risk of high grade AVB occurrence in patients with STEMI. |
10,524 | Depressed Systemic Arterial Compliance is Associated with the Severity of Heart Failure Symptoms in Moderate-to-Severe Aortic Stenosis: a Cross-Sectional Retrospective Study. | Patients with aortic stenosis (AS) may develop heart failure even in the absence of severe valve stenosis. Our aim was to assess the contribution of systemic arterial properties and the global left ventricular afterload to graded heart failure symptoms in AS.</AbstractText>We retrospectively reviewed medical records of 157 consecutive subjects (mean age, 71±10 years; 79 women and 78 men) hospitalized owing to moderate-to-severe degenerative AS. Exclusion criteria included more than mild aortic insufficiency or disease of another valve, atrial fibrillation, coronary artery disease, severe respiratory disease or anemia. Heart failure symptoms were graded by NYHA class at admission. Systemic arterial compliance (SAC) and valvulo-arterial impedance (Zva) were derived from routine echocardiography and blood pressure.</AbstractText>Sixty-one patients were asymptomatic, 49 presented mild (NYHA II) and 47 moderate-to-severe (NYHA III-IV) heart failure symptoms. Mild symptoms were associated with lower SAC and transvalvular gradients, while more severe exercise intolerance coincided with older age, lower systolic blood pressure, smaller aortic valve area and depressed ejection fraction. By multiple ordinal logistic regression, the severity of heart failure symptoms was related to older age, depressed ejection fraction and lower SAC. Each decrease in SAC by 0.1 ml/m² per mmHg was associated with an increased adjusted odds ratio (OR) of a patient being in one higher category of heart failure symptoms graded as no symptoms, mild exercise intolerance and advanced exercise intolerance (OR: 1.16 [95% CI, 1.01-1.35], P=0.045).</AbstractText>Depressed SAC may enhance exercise intolerance irrespective of stenosis severity or left ventricular systolic function in moderate-to-severe AS. This finding supports the importance of non-valvular factors for symptomatic status in AS.</AbstractText> |
10,525 | Dronedarone does not affect infarct volume as assessed by magnetic resonance imaging in a porcine model of myocardial infarction. | Dronedarone has been demonstrated to be harmful in patients with recent decompensated heart failure. Furthermore, a PALLAS study reported that dronedarone therapy increases mortality rates in patients with permanent atrial fibrillation. Although a pathophysiological explanation for these finding remains to be elucidated, the long term effects of dronedarone on myocardial structure and stability have been suggested. The aim of the present study was to determine whether dronedarone therapy affects left ventricular (LV) function in a chronic model of myocardial infarction (MI). An anterior MI was induced in 16 pigs. Of these animals, eight pigs were then treated with dronedarone for 1 week prior to, and 4 weeks following MI, the remaining pigs served as controls. LV angiography was performed 4 weeks after MI to determine the LV ejection fraction (LVEF). A post‑mortem magnetic resonance imaging scan of the LV was then performed on the two groups (n=6) to determine the volume and size of the induced MI. Dronedarone therapy did not affect systemic and intracardiac hemodynamic parameters or LVEF during the follow‑up assessment. Of note, dronedarone had no negative effect on the total infarct volume and size and did not induce lethal proarrhythmic effects following the induced anterior MI. Therefore, the results suggested that dronedarone did not increase the volume or size of induced anterior MI and did not affect LV performance. Thus, dronedarone therapy was observed to be safe in a porcine model of anterior MI. |
10,526 | Effects of Dabigatran on the Resolution of Left Ventricular Thrombus after Acute Myocardial Infarction. | Left ventricular thrombus (LVT) after acute myocardial infarction (AMI) is a risk factor for embolic complications. Although warfarin has traditionally been used to treat LVT, it has relevant disadvantages that limit its use. We herein describe the case of a 78-year-old man with AMI who had a history of paroxysmal atrial fibrillation. Following 10 days of urgent coronary reperfusion therapy, transthoracic echocardiography revealed a moderately sized LVT in the apex, which subsequently disappeared after 18 days of treatment with dabigatran. This case demonstrates that dabigatran may represent an alternative to warfarin as a therapeutic option in patients with LVT after AMI. |
10,527 | Modifying Ventricular Fibrillation by Targeted Rotor Substrate Ablation: Proof-of-Concept from Experimental Studies to Clinical VF. | Recent work has suggested a role for organized sources in sustaining ventricular fibrillation (VF). We assessed whether ablation of rotor substrate could modulate VF inducibility in canines, and used this proof-of-concept as a foundation to suppress antiarrhythmic drug-refractory clinical VF in a patient with structural heart disease.</AbstractText>In 9 dogs, we introduced 64-electrode basket catheters into one or both ventricles, used rapid pacing at a recorded induction threshold to initiate VF, and then defibrillated after 18±8 seconds. Endocardial rotor sites were identified from basket recordings using phase mapping, and ablation was performed at nonrotor (sham) locations (7 ± 2 minutes) and then at rotor sites (8 ± 2 minutes, P = 0.10 vs. sham); the induction threshold was remeasured after each. Sham ablation did not alter canine VF induction threshold (preablation 150 ± 16 milliseconds, postablation 144 ± 16 milliseconds, P = 0.54). However, rotor site ablation rendered VF noninducible in 6/9 animals (P = 0.041), and increased VF induction threshold in the remaining 3. Clinical proof-of-concept was performed in a patient with repetitive ICD shocks due to VF refractory to antiarrhythmic drugs. Following biventricular basket insertion, VF was induced and then defibrillated. Mapping identified 4 rotors localized at borderzone tissue, and rotor site ablation (6.3 ± 1.5 minutes/site) rendered VF noninducible. The VF burden fell from 7 ICD shocks in 8 months preablation to zero ICD therapies at 1 year, without antiarrhythmic medications.</AbstractText>Targeted rotor substrate ablation suppressed VF in an experimental model and a patient with refractory VF. Further studies are warranted on the efficacy of VF source modulation.</AbstractText>© 2015 Wiley Periodicals, Inc.</CopyrightInformation> |
10,528 | Hypertrophic Cardiomyopathy and Implantable Defibrillators in Sweden: Inappropriate Shocks and Complications Requiring Surgery. | The expanded use of implantable cardioverter-defibrillators (ICDs) to prevent sudden cardiac death (SCD) in hypertrophic cardiomyopathy (HCM) based on risk stratification in individuals without known previous ventricular arrhythmia is justified by an acceptable risk of device-related adverse events. Such complications, leading to surgical procedures or inappropriate electrical shocks, may impact mortality, morbidity, quality of life, and cost-effectiveness.</AbstractText>From the Swedish ICD Registry, implants due to HCM since 1995 until November 2012 in patients aged ≥18 years were identified and medical records reviewed. Inappropriate ICD shock occurred in 14.3% (46 of 321 patients; mean follow-up 5.4 years) with a recurrent episode in 28.2% of them. In multivariable analysis, hazard ratio (HR) for atrial fibrillation was 3.5 (95% confidence interval 1.8-6.8; P < 0.001) but showed no significant association to male sex (HR = 0.77), age (HR = 0.99), secondary indication (HR = 1.02) or device, ICD-DR/CRTD vs. ICD-VR (HR 1.07). Inappropriate shocks were triggered by atrial fibrillation/flutter or ectopic tachycardia (56.5%), sinus tachycardia (14.5%), lead dysfunction (14.5%), and T-wave oversensing (13.0%). A reintervention, besides elective device replacement, occurred in 92 patients (totally 150 procedures). The majority were lead-related (70.0%) procedures, especially of the ICD lead. Reintervention was associated with female sex (HR = 1.6 P = 0.04).</AbstractText>Inappropriate ICD shock triggered by atrial arrhythmias, lead dysfunction, or complications requiring surgical interventions, is a concern in HCM patients who will be eligible for long-term prevention of sudden death. Efforts to avoid adverse events and provide balanced risk-benefit information are important, especially in primary prevention.</AbstractText>© 2015 Wiley Periodicals, Inc.</CopyrightInformation> |
10,529 | Possible role for cryoballoon ablation of right atrial appendage tachycardia when conventional ablation fails. | Focal atrial tachycardia arising from the right atrial appendage usually responds well to radiofrequency ablation; however, successful ablation in this anatomic region can be challenging. Surgical excision of the right atrial appendage has sometimes been necessary to eliminate the tachycardia and prevent or reverse the resultant cardiomyopathy. We report the case of a 48-year-old man who had right atrial appendage tachycardia resistant to multiple attempts at ablation with use of conventional radiofrequency energy guided by means of a 3-dimensional mapping system. The condition led to cardiomyopathy in 3 months. The arrhythmia was successfully ablated with use of a 28-mm cryoballoon catheter that had originally been developed for catheter ablation of paroxysmal atrial fibrillation. To our knowledge, this is the first report of cryoballoon ablation without isolation of the right atrial appendage. It might also be an alternative to epicardial ablation or surgery when refractory atrial tachycardia originates from the right atrial appendage. |
10,530 | Catheter Ablation of Idiopathic Epicardial Ventricular Arrhythmias Originating from the Vicinity of the Coronary Sinus System. | Catheter Ablation of Idiopathic Epicardial Ventricular Arrhythmias. Idiopathic epicardial ventricular arrhythmias (IEVAs) originating from the vicinity of the coronary sinus system are not uncommon, accounting for about 9% of idiopathic ventricular arrhythmia cases. IEVAs share clinical presentation and electrophysiological characteristics with ventricular arrhythmias arising from the right ventricular outflow tract possibly as manifestations of cAMP-mediated triggered activity and delayed after-depolarizations. Detailed analysis of standard 12-lead electrocardiogram morphology by using unique variables and algorithms allows clinicians to predict probable location of epicardial foci and informs optimal catheter ablation strategy. Epicardial mapping and ablation through the coronary sinus and its branches is effective and safe, and increasingly favored. However, it is important because of the common perivascular origin of IEVAs to perform coronary angiography prior to or after ablation and to select the appropriate ablation energy form to avoid serious complications. |
10,531 | Impact of Tricuspid Regurgitation on the Success of Atrioventricular Node Ablation for Rate Control in Patients With Atrial Fibrillation: The Node Blast Study. | Atrioventricular node (AVN) ablation is an effective treatment for symptomatic patients with atrial arrhythmias who are refractory to rhythm and rate control strategies where optimal ventricular rate control is desired. There are limited data on the predictors of failure of AVN ablation. Our objective was to identify the predictors of failure of AVN ablation. This is an observational single-center study of consecutive patients who underwent AVN ablation in a large academic center. Baseline characteristics, procedural variables, and outcomes of AVN ablation were collected. AVN "ablation failure" was defined as resumption of AVN conduction resulting in recurrence of either rapid ventricular response or suboptimal biventricular pacing. A total of 247 patients drug refractory AF who underwent AVN ablation at our center with a mean age of 71 ± 12 years with 46% being males were included. Ablation failure was seen in 11 (4.5%) patients. There were no statistical differences between patients with "ablation failure" versus "ablation success" in any of the baseline clinical variables. Patients with moderate-to-severe tricuspid regurgitation (TR) were much more likely to have ablation failure than those with ablation success (8 [73%] vs 65 [27%]; p = 0.003). All 11 patients with ablation failure had a successful redo procedure, 9 with right and 2 with the left sided approach. On multivariate analysis, presence of moderate-to-severe TR was found to be the only predictor of failure of AVN ablation (odds ratio 9.1, confidence interval 1.99 to 42.22, p = 0.004). In conclusion, moderate-to-severe TR is a strong and independent predictor of failure of AVN ablation. |
10,532 | Reduced risk of life-threatening ventricular tachyarrhythmias with cardiac resynchronization therapy: relationship to left ventricular ejection fraction. | We hypothesized that the relationship between LVEF and the risk of life-threatening ventricular tachyarrhythmias (VTAs) may modify the effect of a CRT device with a defibrillator (CRT-D) on VTA risk.</AbstractText>The risk of fast (≥200 b.p.m.) ventricular tachycardia/ventricular fibrillation (VT/VF) and the benefit of CRT-D in reducing VT/VF were assessed by baseline LVEF (categorized as ≤30% or 30% and assessed as a continuous measurement) in 1783 patients with mild heart failure (HF) implanted with an implantable cardioverter defibrillator (ICD) or CRT-D, enrolled in MADIT-CRT. Higher LVEF (>30%) at baseline was associated with a significantly lower risk of fast VT/VF [hazard ratio (HR) 0.54, P = 0.006], VT/VF (HR 0.62, P = 0.005), and VT/VF/death (HR 0.64, P = 0.003). Treatment with CRT-D was shown to reduce the risk of fast VT/VF in patients with LVEF ≤ 30% (n = 1100) [HR 0.64, 95% confidence interval (CI) 0.48-0.85, P = 0.002], but not among those with LVEF > 30% (n = 683) (HR 1.19, 95% CI 0.73-1.91, P = 0.502, interaction P-value = 0.03). When LVEF was assessed as a continuous measure, each 5% increment was shown to be associated with a significant 30% (P < 0.001) reduction in the risk for fast VT/VF, and with a corresponding linear reduction in the benefit of CRT-D in reducing fast VTA risk (P -value for treatment by LVEF interaction = 0.003).</AbstractText>Our data suggest that in mild HF patients with cardiomyopathy there is an inverse correlation between LVEF and the risk of life-threatening VTAs, possibly contributing to the attenuation in the antiarrhythmic properties of CRT with increasing left ventricular function.</AbstractText>NCT00180271.</AbstractText>© 2015 The Authors European Journal of Heart Failure © 2015 European Society of Cardiology.</CopyrightInformation> |
10,533 | Impact of B-type natriuretic peptide (BNP) on development of atrial fibrillation in people with Type 2 diabetes. | To examine if a simple biomarker can identify people with diabetes who are at high risk of atrial fibrillation.</AbstractText>A retrospective cohort study was conducted at a single centre in people with Type 2 diabetes referred to our department between January 2000 and December 2007. In 517 consecutive people without any history, signs or symptoms of atrial fibrillation at baseline, the association between baseline B-type natriuretic peptide level and future atrial fibrillation incidence was examined, with adjustments for other potentially confounding factors.</AbstractText>A total of 28 people were diagnosed with new-onset atrial fibrillation during a median 6-year follow-up. When people were categorized into three groups according to B-type natriuretic peptide clinical thresholds (20 and 100 pg/ml), hazard ratios for the development of atrial fibrillation in the middle and highest B-type natriuretic peptide groups were 2.8 and 9.4, respectively, compared with the lowest B-type natriuretic peptide group. Time-dependent receiver-operating curve analysis identified a threshold for B-type natriuretic peptide to detect atrial fibrillation development of 52.8 pg/ml (sensitivity 75.2%, specificity 68.8%). The B-type natriuretic peptide predictive value was independent of and similar to that of left atrial size and ventricular dimension.</AbstractText>In people with Type 2 diabetes, high baseline B-type natriuretic peptide levels were significantly associated with future atrial fibrillation development.</AbstractText>© 2015 Diabetes UK.</CopyrightInformation> |
10,534 | Long-Term Effects of Atrial Ganglionated Plexi Ablation on Function and Structure of Sinoatrial and Atrioventricular Node in Canine. | Long-term effects of ganglionated plexi (GP) ablation on sinoatrial node (SAN) and atrioventricular node (AVN) remain unclear. This study is to investigate the long-term effects of ablation of cardiac anterior right GP (ARGP) and inferior right GP (IRGP) on function and structure of SAN and AVN in canine.</AbstractText>Thirty-two dogs were randomly divided into an operated group (n = 24) and sham-operated group (n = 8). ARGP and IRGP were ablated in operated group which was randomly divided into three subgroups according to the period of evaluation after operation (1 month, 6 months, 12 months). The functional and histological characteristics of SAN and AVN, as well as the expression of connexin (Cx) 43 and Cx 45 in SAN and AVN, were evaluated before and after ablation.</AbstractText>Resting heart rate was increased and AVN effective refractory period was prolonged and sinus node recovery time (SNRT) and corrected SNRT were shortened immediately after ablation. These changes were reverted to preablation level after 1 month. At 1 month, ventricular rate during atrial fibrillation was slowed, atria-His intervals were prolonged, and Cx43 and Cx45 expression in SAN and AVN were downregulated. At 6 months, all changes were reverted to preablation level. The histological characteristics of SAN and AVN did not change.</AbstractText>Ablation of ARGP and IRGP has short-term effects on function and structure of SAN and AVN rather than long-term effects, which suggests that ablation of ARGP and IRGP is safe. Atrioventricular conduction dysfunction after ablation may be related to downregulated Cx43 and Cx45 expression in AVN.</AbstractText>© 2015 Wiley Periodicals, Inc.</CopyrightInformation> |
10,535 | Beneficial Effects of Isoproterenol and Quinidine in the Treatment of Ventricular Fibrillation in Brugada Syndrome. | The use of an implantable cardiac defibrillator has been advocated as the only effective treatment for the management of ventricular fibrillation (VF) in patients with Brugada Syndrome (BrS). However, this device is only useful for terminating VF. Intermittent and/or recalcitrant VF for which lifesaving cardioversion occurs is a problematic situation in this patient population. The immediate use of appropriate antiarrhythmics in the acute setting has proven to be lifesaving. Quinidine has been well established as an effective antiarrhythmic in BrS, while isoproterenol (ISP) has had some recognition as well. The addition of drug therapy to prevent the induction of these arrhythmias has been shown to reduce the morbidity and mortality associated with BrS. It was proven to be especially effective in the presence of early repolarization, evidenced by the reduction or normalization of the early repolarization pattern on ECG. Thus, for the prophylactic management and long term suppression of VF in BrS, further prospective studies should be performed to determine the effectiveness of quinidine and ISP in this patient population. |
10,536 | Preconditioning with PEP-1-SOD1 fusion protein attenuates ischemia/reperfusion-induced ventricular arrhythmia in isolated rat hearts. | PEP 1-Cu/Zn superoxide dismutase (PEP-1-SOD1) fusion protein preconditioning has been reported to protect the myocardium from ischemia/reperfusion (I/R)-induced injury by decreasing the infarct size, reducing levels of cardiomyocyte apoptosis and reducing the release of myocardial-specific biomarkers. The aim of the present study was to examine the effects of PEP-1-SOD1 pretreatment on I/R-induced ventricular arrhythmias in Langendorff-perfused rat hearts. The isolated rat hearts were pretreated with PEP-1-SOD1 prior to I/R, and the I/R-induced hemodynamic parameters, infarct size and ventricular arrhythmias were then assessed. Compared with the unprotected hearts, PEP-1-SOD1 preconditioning significantly improved the hemodynamic parameters, decreased the cardiac lactate dehydrogenase and creatine kinase-MB (CK-MB) levels, reduced the infarct size and attenuated the ventricular arrhythmia. Further investigation showed that PEP-1-SOD1 preconditioning reduced both the incidence and duration of ventricular tachycardia/ventricular fibrillation. In addition, the intracellular reactive oxygen species (ROS) levels were decreased. The results of the present study suggest that PEP-1-SOD1 preconditioning can protect the heart against I/R injury and attenuate I/R-induced arrhythmia by downregulating the generation of ROS. |
10,537 | Diet-induced pre-diabetes slows cardiac conductance and promotes arrhythmogenesis. | Type 2 diabetes is associated with abnormal electrical conduction and sudden cardiac death, but the pathogenic mechanism remains unknown. This study describes electrophysiological alterations in a diet-induced pre-diabetic rat model and examines the underlying mechanism.</AbstractText>Sprague-Dawley rats were fed either high-fat diet and fructose water or normal chow and water for 6 weeks. The electrophysiological properties of the whole heart was analyzed by in vivo surface ECG recordings, as wells as ex vivo in Langendorff perfused hearts during baseline, ischemia and reperfussion. Conduction velocity was examined in isolated tissue strips. Ion channel and gap junction conductances were analyzed by patch-clamp studies in isolated cardiomyocytes. Fibrosis was examined by Masson's Trichrome staining and thin-layer chromatography was used to analyze cardiac lipid content. Connexin43 (Cx43) expression and distribution was examined by western blotting and immunofluorescence respectively.</AbstractText>Following 6 weeks of feeding, fructose-fat fed rats (FFFRs) showed QRS prolongation compared to controls (16.1 ± 0.51 (n = 6) vs. 14.7 ± 0.32 ms (n = 4), p < 0.05). Conduction velocity was slowed in FFFRs vs. controls (0.62 ± 0.02 (n = 13) vs. 0.79 ± 0.06 m/s (n = 11), p < 0.05) and Langendorff perfused FFFR hearts were more prone to ventricular fibrillation during reperfusion following ischemia (p < 0.05). The patch-clamp studies revealed no changes in Na(+) or K(+) currents, cell capacitance or gap junctional coupling. Cx43 expression was also unaltered in FFFRs, but immunofluorescence demonstrated an increased fraction of Cx43 localized at the intercalated discs in FFFRs compared to controls (78 ± 3.3 (n = 5) vs. 60 ± 4.2 % (n = 6), p < 0.01). No fibrosis was detected but FFFRs showed a significant increase in cardiac triglyceride content (1.93 ± 0.19 (n = 12) vs. 0.77 ± 0.13 nmol/mg (n = 12), p < 0.0001).</AbstractText>Six weeks on a high fructose-fat diet cause electrophysiological changes, which leads to QRS prolongation, decreased conduction velocity and increased arrhythmogenesis during reperfusion. These alterations are not explained by altered gap junctional coupling, Na(+), or K(+) currents, differences in cell size or fibrosis.</AbstractText> |
10,538 | Ventricular Fibrillation Precipitated by Intracoronary Adenosine During Fractional Flow Reserve Assessment - A Cautionary Tale. | Fractional flow reserve (FFR) measurement is the current benchmark for assessing the physiologic significance of a coronary stenosis. Intravenous / intra-coronary adenosine is a commonly used agent to induce hyperaemia, required for FFR measurement. In our institute, we have observed three cases of ventricular fibrillation (VF) after intra-coronary adenosine injection. Volume of the injections appeared to be the responsible mechanism, supported by evidence from optical coherence tomography (OCT) experience. Since doubling the concentration of adenosine to reduce the volume of injection by half, no further incidence of VF has been noted. |
10,539 | Infarct transmurality as a criterion for first-line endo-epicardial substrate-guided ventricular tachycardia ablation in ischemic cardiomyopathy.<Pagination><StartPage>85</StartPage><EndPage>95</EndPage><MedlinePgn>85-95</MedlinePgn></Pagination><ELocationID EIdType="doi" ValidYN="Y">10.1016/j.hrthm.2015.07.010</ELocationID><ELocationID EIdType="pii" ValidYN="Y">S1547-5271(15)00892-9</ELocationID><Abstract><AbstractText Label="BACKGROUND" NlmCategory="BACKGROUND">There is no consensus on the appropriate indications for the epicardial approach in substrate ablation of post-myocardial infarction (MI) ventricular tachycardia (VT).</AbstractText><AbstractText Label="OBJECTIVE" NlmCategory="OBJECTIVE">The purpose of this study was to investigate whether infarct transmurality (IT) could identify patients who would benefit from a combined first-line endo-epicardial approach.</AbstractText><AbstractText Label="METHODS" NlmCategory="METHODS">Before ablation, IT was assessed by contrast-enhanced cardiac magnetic resonance imaging (hyperenhancement ≥75% of the wall thickness in ≥1 segment), echocardiography (dyskinesia/akinesia + hyperrefringency + wall thinning), computed tomography (wall thinning), or scintigraphy (transmural necrosis). Prospectively from January 2011, an endocardial approach was used in patients with subendocardial MI (group 1) and a combined endo-epicardial approach in patients with transmural MI (group 2). Outcomes in both groups were compared with those in patients with transmural MI and only endocardial approach due to previous cardiac surgery or procedure performed before January 2011 (group 3). The primary end point was VT/ventricular fibrillation recurrence-free survival.</AbstractText><AbstractText Label="RESULTS" NlmCategory="RESULTS">Ninety patients (92.2% men; mean age 67.4 ± 9.8 years) undergoing VT substrate ablation were included: group 1, n = 34; group 2, n = 24; group 3, n = 32. During a mean follow-up duration of 22.5 ± 13.7 months, 5 patients in group 1 (14.7%), 3 patients in group 2 (12.5%), and 13 patients in group 3 (40.6%) had VT recurrences (P = .011). Time to recurrence was the shortest in group 3 (log-rank, P = .018). The endocardial approach in patients with transmural MI was associated with an increased risk of recurrence (hazard ratio 4.01; 95% confidence interval 1.41-11.3; P = .009).</AbstractText><AbstractText Label="CONCLUSION" NlmCategory="CONCLUSIONS">The endocardial approach in patients with transmural MI undergoing VT substrate ablation is associated with an increased risk of recurrence. IT may be a useful criterion for the selection of a first-line combined endo-epicardial approach.</AbstractText><CopyrightInformation>Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation></Abstract><AuthorList CompleteYN="Y"><Author ValidYN="Y"><LastName>Acosta</LastName><ForeName>Juan</ForeName><Initials>J</Initials><AffiliationInfo><Affiliation>Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), University of Barcelona, Catalonia, Spain.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Fernández-Armenta</LastName><ForeName>Juan</ForeName><Initials>J</Initials><AffiliationInfo><Affiliation>Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), University of Barcelona, Catalonia, Spain.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Penela</LastName><ForeName>Diego</ForeName><Initials>D</Initials><AffiliationInfo><Affiliation>Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), University of Barcelona, Catalonia, Spain.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Andreu</LastName><ForeName>David</ForeName><Initials>D</Initials><AffiliationInfo><Affiliation>Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), University of Barcelona, Catalonia, Spain.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Borras</LastName><ForeName>Roger</ForeName><Initials>R</Initials><AffiliationInfo><Affiliation>Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), University of Barcelona, Catalonia, Spain.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Vassanelli</LastName><ForeName>Francesca</ForeName><Initials>F</Initials><AffiliationInfo><Affiliation>Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), University of Barcelona, Catalonia, Spain.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Korshunov</LastName><ForeName>Viatcheslav</ForeName><Initials>V</Initials><AffiliationInfo><Affiliation>Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), University of Barcelona, Catalonia, Spain.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Perea</LastName><ForeName>Rosario J</ForeName><Initials>RJ</Initials><AffiliationInfo><Affiliation>Radiology Department, Hospital Clinic, University of Barcelona, Barcelona, Catalonia, Spain.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>de Caralt</LastName><ForeName>Teresa M</ForeName><Initials>TM</Initials><AffiliationInfo><Affiliation>Radiology Department, Hospital Clinic, University of Barcelona, Barcelona, Catalonia, Spain.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Ortiz</LastName><ForeName>Jose T</ForeName><Initials>JT</Initials><AffiliationInfo><Affiliation>Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), University of Barcelona, Catalonia, Spain.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Fita</LastName><ForeName>Guillermina</ForeName><Initials>G</Initials><AffiliationInfo><Affiliation>Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), University of Barcelona, Catalonia, Spain.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Sitges</LastName><ForeName>Marta</ForeName><Initials>M</Initials><AffiliationInfo><Affiliation>Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), University of Barcelona, Catalonia, Spain.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Brugada</LastName><ForeName>Josep</ForeName><Initials>J</Initials><AffiliationInfo><Affiliation>Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), University of Barcelona, Catalonia, Spain.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Mont</LastName><ForeName>Lluis</ForeName><Initials>L</Initials><AffiliationInfo><Affiliation>Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), University of Barcelona, Catalonia, Spain.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Berruezo</LastName><ForeName>Antonio</ForeName><Initials>A</Initials><AffiliationInfo><Affiliation>Arrhythmia Section, Cardiology Department, Thorax Institute, Hospital Clínic and IDIBAPS (Institut d'Investigació Agustí Pi i Sunyer), University of Barcelona, Catalonia, Spain,. Electronic address: berruezo@clinic.ub.es.</Affiliation></AffiliationInfo></Author></AuthorList><Language>eng</Language><PublicationTypeList><PublicationType UI="D016428">Journal Article</PublicationType></PublicationTypeList><ArticleDate DateType="Electronic"><Year>2015</Year><Month>07</Month><Day>09</Day></ArticleDate></Article><MedlineJournalInfo><Country>United States</Country><MedlineTA>Heart Rhythm</MedlineTA><NlmUniqueID>101200317</NlmUniqueID><ISSNLinking>1547-5271</ISSNLinking></MedlineJournalInfo><CitationSubset>IM</CitationSubset><MeshHeadingList><MeshHeading><DescriptorName UI="D000368" MajorTopicYN="N">Aged</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D017115" MajorTopicYN="Y">Catheter Ablation</DescriptorName><QualifierName UI="Q000009" MajorTopicYN="N">adverse effects</QualifierName><QualifierName UI="Q000379" MajorTopicYN="N">methods</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D004699" MajorTopicYN="Y">Endocardium</DescriptorName><QualifierName UI="Q000503" MajorTopicYN="N">physiopathology</QualifierName><QualifierName UI="Q000601" MajorTopicYN="N">surgery</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D056149" MajorTopicYN="N">Epicardial Mapping</DescriptorName><QualifierName UI="Q000379" MajorTopicYN="Y">methods</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D005260" MajorTopicYN="N">Female</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D005500" MajorTopicYN="N">Follow-Up Studies</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D006801" MajorTopicYN="N">Humans</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D008297" MajorTopicYN="N">Male</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D008875" MajorTopicYN="N">Middle Aged</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D009203" MajorTopicYN="N">Myocardial Infarction</DescriptorName><QualifierName UI="Q000150" MajorTopicYN="Y">complications</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D016016" MajorTopicYN="N">Proportional Hazards Models</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D012008" MajorTopicYN="N">Recurrence</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D017180" MajorTopicYN="Y">Tachycardia, Ventricular</DescriptorName><QualifierName UI="Q000175" MajorTopicYN="N">diagnosis</QualifierName><QualifierName UI="Q000209" MajorTopicYN="N">etiology</QualifierName><QualifierName UI="Q000601" MajorTopicYN="N">surgery</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D016896" MajorTopicYN="N">Treatment Outcome</DescriptorName></MeshHeading></MeshHeadingList><KeywordList Owner="NOTNLM"><Keyword MajorTopicYN="N">Epicardial approach</Keyword><Keyword MajorTopicYN="N">Infarct transmurality</Keyword><Keyword MajorTopicYN="N">Ventricular tachycardia ablation</Keyword></KeywordList></MedlineCitation><PubmedData><History><PubMedPubDate PubStatus="received"><Year>2015</Year><Month>5</Month><Day>26</Day></PubMedPubDate><PubMedPubDate PubStatus="entrez"><Year>2015</Year><Month>7</Month><Day>14</Day><Hour>6</Hour><Minute>0</Minute></PubMedPubDate><PubMedPubDate PubStatus="pubmed"><Year>2015</Year><Month>7</Month><Day>15</Day><Hour>6</Hour><Minute>0</Minute></PubMedPubDate><PubMedPubDate PubStatus="medline"><Year>2016</Year><Month>10</Month><Day>1</Day><Hour>6</Hour><Minute>0</Minute></PubMedPubDate></History><PublicationStatus>ppublish</PublicationStatus><ArticleIdList><ArticleId IdType="pubmed">26165946</ArticleId><ArticleId IdType="doi">10.1016/j.hrthm.2015.07.010</ArticleId><ArticleId IdType="pii">S1547-5271(15)00892-9</ArticleId></ArticleIdList></PubmedData></PubmedArticle><PubmedArticle><MedlineCitation Status="MEDLINE" Owner="NLM"><PMID Version="1">26165008</PMID><DateCompleted><Year>2015</Year><Month>09</Month><Day>15</Day></DateCompleted><DateRevised><Year>2016</Year><Month>11</Month><Day>25</Day></DateRevised><Article PubModel="Print"><Journal><ISSN IssnType="Print">0042-4676</ISSN><JournalIssue CitedMedium="Print"><Issue>2</Issue><PubDate><Year>2015</Year><Season>Mar-Apr</Season></PubDate></JournalIssue><Title>Vestnik rentgenologii i radiologii</Title><ISOAbbreviation>Vestn Rentgenol Radiol</ISOAbbreviation></Journal>[Capabilities of radiodiagnostic techniques for evaluating myocardial hemodynamics and contractility in ventricular arrhythmias]. | As of now, the study of ventricular arrhythmias (VA) is of topical interest for modern arrhythmology and cardiology. These arrhythmias constitute about 30% of all the arrhythmias and have a diverse etiopathogenetic basis. Having no noticeable impact on a patient's quality of life, VA may cause ventricular fibrillation, severe circulatory disorders, and sudden cardiac death. Objective of this study--to compare the capabilities of radiation techniques for evaluating ventricular hemodynamics and contractility in patients with VA. A multitude of current radiodiagnostic methods, among which the most preferential technique cannot be set aside to reveal the causes of and to study hemodynamic disorders, is now used to evaluate ventricular hemodynamics and contractility in patients with VA. Each procedure has its usage features in a contingent of patients with arrhythmias. |
10,540 | Combination of initial neurologic examination and continuous EEG to predict survival after cardiac arrest. | Prognosticating outcome following cardiac arrest requires a multimodal approach. We tested whether the combination of initial neurologic examination combined with continuous EEG was superior to either test alone for predicting survival after cardiac arrest.</AbstractText>Review of consecutive patients receiving continuous EEG monitoring between April 2010 and June 2013. Initial neurologic examination was evaluated using the Full Outline of UnResponsiveness (FOUR) score and organ system dysfunction determined using the SOFA score. We defined four categories of initial post-cardiac arrest illness severity (PCAC): (I) awake, (II) coma (not following commands but intact brainstem responses) + mild cardiopulmonary dysfunction (SOFA cardiac + respiratory score < 4), (III) coma + moderate-severe cardiopulmonary dysfunction (SOFA cardiac + respiratory score ≥ 4), and (IV) coma without brainstem reflexes. A second analysis focusing on neurologic injury divided subjects into three groups according to initial FOUR_B score; FOUR_B = 0-1, FOUR_B = 2 and FOUR_B = 4. A blinded rater dichotomized continuous EEG patterns during the first 48h into malignant patterns (non-convulsive status epilepticus, convulsive status epilepticus, myoclonic status epilepticus and generalized periodic epileptiform discharges). The primary outcome was survival to hospital discharge.</AbstractText>Of 331 subjects, mean age was 58 (SD 17) years and 206 (62.2%) subjects were male. Ventricular fibrillation or tachycardia (VF/VT) was the initial rhythm for 93 (28.1%) subjects. Among subjects with malignant cEEG, survival to hospital discharge rate was 0% for FOUR_B 0-1, 8.1% for FOUR_B 2 and 12.5% for FOUR_B 4, respectively. In one multivariate analysis, survival was independently associated with VF/VT, FOUR_B of 2, FOUR_B of 4, and non-malignant cEEG. In a separate model, survival was associated with VF/VT, PCAC < 4 and non-malignant cEEG. The AUCs of FOUR_B, cEEG and the combination of FOUR_B and cEEG are 0.740 (95% C.I. 0.684-0.797), 0.674 (95% C.I. 0.615-0.732) and 0.820 (95% C.I. 0.773-0.868) respectively. The AUCs of PCAC, cEEG and the combination of PCAC and cEEG are 0.779 (95% C.I. 0.721-0.838), 0.672 (95% C.I. 0.612-0.7321) and 0.846 (95% C.I. 0.798-0.894) respectively.</AbstractText>Combining the initial neurologic examination using either FOUR_B or PCAC, with cEEG was superior to any individual test for predicting survival after cardiac arrest. We caution against using these findings to speed prognostication until they are externally validated.</AbstractText>Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
10,541 | Distinctive malfunctions of calmodulin mutations associated with heart RyR2-mediated arrhythmic disease. | Calmodulin (CaM) is a cytoplasmic calcium sensor that interacts with the cardiac ryanodine receptor (RyR2), a large Ca(2+) channel complex that mediates Ca(2+) efflux from the sarcoplasmic reticulum (SR) to activate cardiac muscle contraction. Direct CaM association with RyR2 is an important physiological regulator of cardiac muscle excitation-contraction coupling and defective CaM-RyR2 protein interaction has been reported in cases of heart failure. Recent genetic studies have identified CaM missense mutations in patients with a history of severe cardiac arrhythmogenic disorders that present divergent clinical features, including catecholaminergic polymorphic ventricular tachycardia (CPVT), long QT syndrome (LQTS) and idiopathic ventricular fibrillation (IVF). Herein, we describe how two CPVT- (N54I & N98S) and three LQTS-associated (D96V, D130G & F142L) CaM mutations result in alteration of their biochemical and biophysical properties. Ca(2+)-binding studies indicate that the CPVT-associated CaM mutations, N54I & N98S, exhibit the same or a 3-fold reduced Ca(2+)-binding affinity, respectively, versus wild-type CaM, whereas the LQTS-associated CaM mutants, D96V, D130G & F142L, display more profoundly reduced Ca(2+)-binding affinity. In contrast, all five CaM mutations confer a disparate RyR2 interaction and modulation of [(3)H]ryanodine binding to RyR2, regardless of CPVT or LQTS association. Our findings suggest that the clinical presentation of CPVT or LQTS associated with these five CaM mutations may involve both altered intrinsic Ca(2+)-binding as well as defective interaction with RyR2. |
10,542 | Resting 12-lead electrocardiogram reveals high-risk sources of cardioembolism in young adult ischemic stroke. | The diagnostic work-up to reveal etiology in a young ischemic stroke (IS) patient includes evaluation for high-risk source of cardioembolism (HRCE), since this subtype associates with high early recurrence rate and mortality. We investigated the association of ECG findings with a final etiologic subgroup of HRCE in a cohort of young patients with first-ever IS.</AbstractText>The Helsinki Young Stroke Registry includes IS patients aged 15 to 49 years admitted between 1994 and 2007. Blinded to other clinical data, we analyzed a 12-lead resting ECG obtained 1-14 days after the onset of stroke symptoms in 690 patients. We then compared the ECG findings between a final diagnosis of HRCE (n=78) and other/undetermined causes (n=612). We used multivariate logistic regression to study the association between ECG parameters and HRCE.</AbstractText>Of our cohort (63% male), 35% showed ECG abnormality, the most common being T-wave inversion (16%), left ventricular hypertrophy (14%), prolonged P-wave (13%), and prolonged QTc (12%). 3% had atrial fibrillation (AF), and 4% P-terminal force (PTF). Of the continuous parameters, longer QRS-duration, QTc, and wider QRS-T-angle independently associated with HRCE. After AF, PTF had the strongest independent association with HRCE (odds ratio=44.32, 95% confidence interval=[10.51-186.83]), followed by a QRS-T angle >110° (8.29 [3.55-19.32]), T-wave inversion (5.06, 2.54-10.05), and prolonged QTc (3.02 [1.39-6.56]).</AbstractText>Routine ECG provides useful information for directing the work-up of a young IS patient. In addition to AF, PTF in particular showed a strong association with etiology of HRCE.</AbstractText>Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
10,543 | Myocardial depression induced by severe sepsis: successful rescue using extracorporeal cardiopulmonary resuscitation from initial phase of severe sepsis. | A 60-year-old man was diagnosed with severe sepsis caused by pyelonephritis. During transfer to the hospital room, he suddenly developed ventricular fibrillation and the patient recovered after electrical defibrillation. After this cardiac event, his haemodynamics collapsed despite administration of crystalloid fluid. Transthoracic echocardiography was immediately performed showing the oedema and reduced left ventricular wall motion. Since the haemodynamic collapse was too severe to maintain with conventional septic shock therapy, we introduced extracorporeal cardiopulmonary resuscitation, bridging to administration of antibiotics. As a result of these combined therapies, the patient was successfully resuscitated. From this clinical course, we finally diagnosed that the severe sepsis was concomitant with myocardial depression. Introduction of mechanical support, including extracorporeal cardiopulmonary resuscitation may be recommendable in cases of severe sepsis with myocardial depression resulting in haemodynamic collapse, however, the option of introduction of an invasive approach needs further examination. |
10,544 | Hydrogen Sulfide Inhalation Improves Neurological Outcome via NF-κB-Mediated Inflammatory Pathway in a Rat Model of Cardiac Arrest and Resuscitation. | <AbstractText Label="BACKGROUND/AIMS" NlmCategory="OBJECTIVE">The effects of H2S on cerebral inflammatory reaction after cardiac arrest (CA) and cardiopulmonary resuscitation (CPR) remain poorly understood. In this study, we investigated the effects of exogenous 40 ppm and 80 ppm H2S gas on inflammatory reaction and neurological outcome after CA/CPR.</AbstractText>CA was induced by ventricular fibrillation and followed by CPR. Forty or 80 ppm H2S was inhaled for 1 h immediately following CPR. The levels of IL-1β, IL-6 and TNF-α, the myeloperoxidase (MPO) activity, the expression of iNOS and ICAM-1, and the phosphorylation and translocation of NF-κB were evaluated at 24 h after CA/ CPR. The tape removal test, survival rate and hippocampal neuronal counts were investigated at 14 d after CA/CPR.</AbstractText>CA/CPR induced significant increases in IL-1β, IL-6, TNF-α and MPO activity. The phosphorylation and translocation of NF-κB, and the expression of iNOS and ICAM-1 were increased significantly. Inhalation of 40 or 80 ppm H2S gas decreased these inflammatory cytokines. Furthermore, 40 or 80 ppm H2S inhibited the activation of NF-κB and the downstream proinflammatory mediators iNOS and ICAM-1. H2S inhalation also improved neurological function, 14-d survival rate, and reduced hippocampal neuronal loss.</AbstractText>These results indicated that inhalation of H2S protected against brain injury after CA/CPR. The mechanisms underlying protective effects of H2S were associated with the inhibition of CA/ CPR-induced inflammation reactions by reducing IL-1β, IL-6 and TNF-α, and concomitantly inhibiting the activation and infiltration of neutrophils. The beneficial effects of H2S might be mediated by downregulation of NF-κB and the downstream proinflammatory signaling pathway.</AbstractText>© 2015 S. Karger AG, Basel.</CopyrightInformation> |
10,545 | Huge Left Atrium Accompanied by Normally Functioning Prosthetic Valve. | Giant left atria are defined as those measuring larger than 8 cm and are typically found in patients who have rheumatic mitral valve disease with severe regurgitation. Enlargement of the left atrium may create compression of the surrounding structures such as the esophagus, pulmonary veins, respiratory tract, lung, inferior vena cava, recurrent laryngeal nerve, and thoracic vertebrae and lead to dysphagia, respiratory dysfunction, peripheral edema, hoarse voice, or back pain. However, a huge left atrium is usually associated with rheumatic mitral valve disease but is very rare in a normally functioning prosthetic mitral valve, as was the case in our patient. A 46-year-old woman with a past medical history of mitral valve replacement and chronic atrial fibrillation was admitted to our hospital with a chief complaint of cough and shortness of breath, worsened in the last month. Physical examination showed elevated jugular venous pressure, respiratory distress, cardiac cachexia, heart failure, hepatomegaly, and severe edema in the legs. Chest radiography revealed an inconceivably huge cardiac sell-out. Transthoracic echocardiography demonstrated a huge left atrium, associated with thrombosis, and normal function of the prosthetic mitral valve. Cardiac surgery with left atrial exploration for the extraction of the huge thrombosis and De Vega annuloplasty for tricuspid regurgitation were carried out. The postoperative course was eventful due to right ventricular failure and low cardiac output syndrome; and after two days, the patient expired with multiple organ failure. Thorough literature review showed that our case was the largest left atrium (20 × 22 cm) reported thus far in adults with a normal prosthetic mitral valve function. |
10,546 | Refractory ventricular fibrillation managed by coronary revascularisation performed during ongoing manual cardiac resuscitation lasting 1½ h. | Myocardial infarction is the most common cause of ventricular arrhythmias. Although there have been several improvements and refinements in coronary catheterisation with percutaneous intervention over the years, this intervention is still rarely considered during active ongoing resuscitation of patients, especially in cases of persistent ventricular arrhythmias. We present a case of refractory ventricular fibrillations due to in-stent thrombosis that was managed by emergent coronary angiogram and stent placement during ongoing cardiopulmonary resuscitation in a code that lasted about 1½ h. The patient subsequently made an excellent recovery and was discharged home 13 days later. |
10,547 | [Ventricular aneurysm as a complication of giant cell myocarditis]. | Ventricular aneurysm as late complication has been described in cardiac sarcoidosis and occasionally in giant cell myocarditis. The images from the present case of ventricular aneurysm formation as a late complication of giant cell myocarditis underline a potential cause of sudden arrhythmic death in patients who survive this life-threatening condition in the absence of recurrent inflammation and with preserved left ventricular ejection fraction. Follow-up with cardiac magnetic resonance can detect small aneurysms, and an implantable cardioverter-defibrillator may be considered when this complication occurs. |
10,548 | [Algorithm for the management of patients with ventricular arrhythmias]. | The paper proposes an original algorithm for the management of patients with ventricular arrhythmia from its first registration to choice of treatment policy. Using modern diagnostic methods, much attention is paid to the identification of myocardial structural and ischemic changes and also to the involvement of the autonomic and central nervous systems in ventricular arrhythmogenesis. The diagnostic problems are solved step-by-step. The role of psychological diagnosis is accentuated. Longitudinal electrocardiogram monitoring with telemetric data transmission can promptly initiate treatment of patients in an outpatient setting and, in a number of cases, without discontinuing work. The key point of the algorithm proposed is to prevent sudden cardiac death.</Abstract><AuthorList CompleteYN="Y"><Author ValidYN="Y"><LastName>Shlyakhto</LastName><ForeName>E V</ForeName><Initials>EV</Initials><AffiliationInfo><Affiliation>Federal North-West Medical Research Center, Ministry of Health of the Russian Federation, Saint Petersburg.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Treshkur</LastName><ForeName>T V</ForeName><Initials>TV</Initials><AffiliationInfo><Affiliation>Federal North-West Medical Research Center, Ministry of Health of the Russian Federation, Saint Petersburg.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Tulintseva</LastName><ForeName>T E</ForeName><Initials>TE</Initials><AffiliationInfo><Affiliation>Federal North-West Medical Research Center, Ministry of Health of the Russian Federation, Saint Petersburg.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Zhdanova</LastName><ForeName>O N</ForeName><Initials>ON</Initials><AffiliationInfo><Affiliation>Acad. I.P. Pavlov First Saint Petersburg State Medical University, Ministry of Health of the Russian Federation, Saint Petersburg, Russia.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Tikhonenko</LastName><ForeName>V M</ForeName><Initials>VM</Initials><AffiliationInfo><Affiliation>Federal North-West Medical Research Center, Ministry of Health of the Russian Federation, Saint Petersburg.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Tsurinova</LastName><ForeName>E A</ForeName><Initials>EA</Initials><AffiliationInfo><Affiliation>Federal North-West Medical Research Center, Ministry of Health of the Russian Federation, Saint Petersburg.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Ilyina</LastName><ForeName>D Yu</ForeName><Initials>DY</Initials><AffiliationInfo><Affiliation>Federal North-West Medical Research Center, Ministry of Health of the Russian Federation, Saint Petersburg.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Los</LastName><ForeName>M M</ForeName><Initials>MM</Initials><AffiliationInfo><Affiliation>Federal North-West Medical Research Center, Ministry of Health of the Russian Federation, Saint Petersburg.</Affiliation></AffiliationInfo></Author></AuthorList><Language>rus</Language><PublicationTypeList><PublicationType UI="D004740">English Abstract</PublicationType><PublicationType UI="D016428">Journal Article</PublicationType><PublicationType UI="D016454">Review</PublicationType></PublicationTypeList></Article><MedlineJournalInfo><Country>Russia (Federation)</Country><MedlineTA>Ter Arkh</MedlineTA><NlmUniqueID>2984818R</NlmUniqueID><ISSNLinking>0040-3660</ISSNLinking></MedlineJournalInfo><CitationSubset>IM</CitationSubset><MeshHeadingList><MeshHeading><DescriptorName UI="D000465" MajorTopicYN="Y">Algorithms</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D006801" MajorTopicYN="N">Humans</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D014693" MajorTopicYN="N">Ventricular Fibrillation</DescriptorName><QualifierName UI="Q000175" MajorTopicYN="Y">diagnosis</QualifierName><QualifierName UI="Q000628" MajorTopicYN="Y">therapy</QualifierName></MeshHeading></MeshHeadingList><OtherAbstract Type="Publisher" Language="rus">В работе предлагается оригинальный алгоритм ведения пациентов с желудочковой аритмией - от момента ее первой регистрации до выбора лечебной тактики. Большое внимание уделяется выявлению структурных и ишемических изменений миокарда с применением современных методов исследования, а также участию вегетативной и центральной нервной системы в желудочковом аритмогенезе, поэтапно решаются диагностические задачи. Выделяется роль психологической диагностики. Многосуточное мониторирование (электрокардиограмма с телеметрией) позволяет оперативно приступить к этапу лечения пациента, проводить его в амбулаторных условиях, а в ряде случаев - и без отрыва от трудовой деятельности. Ключевой момент предложенного алгоритма - профилактика внезапной сердечной смерти. |
10,549 | Aborted sudden cardiac death associated with an anomalous right coronary artery. | Coronary artery anomalies arising from the opposite sinus of Valsalva and having an interarterial course between the aorta (AO) and pulmonary artery (PA) are the second most common cause of sudden cardiac death among young athletes, after hypertrophic cardiomyopathy. The right coronary artery (RCA) originating from the AO above the left sinus of Valsalva (LSV) is an extremely rare anomaly. We report the first case of a RCA arising from the AO above the LSV that subsequently runs between the AO and the PA, discovered by a 64-slice multidetector coronary CT, in a patient who was successfully resuscitated from ventricular fibrillation (VF) cardiac arrest while running in a marathon race. |
10,550 | Factors Associated With and Outcomes After Ventricular Fibrillation Before and During Primary Angioplasty in Patients With ST-Segment Elevation Myocardial Infarction. | We aimed to assess the risk factors and outcome of ventricular fibrillation (VF) before and during primary percutaneous coronary intervention (PPCI) in patients with ST-segment elevation myocardial infarction. From 1999 to 2012, we consecutively enrolled 5,373 patients with ST-segment elevation myocardial infarction. In total, 410 of the patients had VF before and 88 had VF during PPCI. During a mean follow-up of 4.2 years, 1,196 subjects died. A logistic regression model identified younger age, anterior infarct, Killip class >I at admission, and a preprocedural Thrombolysis In Myocardial Infarction flow grade of 0 to I to be significantly associated with VF before PPCI, whereas inferior infarct, a preprocedural Thrombolysis In Myocardial Infarction flow grade of 0 to I, and Killip class >I at admission were significantly associated with VF during PPCI. All-cause mortality was evaluated using the Cox regression model. Compared with the patients without VF, those with VF before or during PPCI had a significantly increased 30-day mortality, with an adjusted hazard ratio = 3.40 (95% confidence interval 1.70 to 6.70) and 4.20 (95% confidence interval 1.30 to 13.30), respectively. Importantly, there was no tendency of 30-day mortality difference between VF before and during PPCI (p = 0.170). In patients with VF before or during PPCI who survived for at least 30 days, there was no increase in the long-term mortality. In conclusion, our data suggest that 30-day mortality is the same for patients with VF before PPCI compared with VF during PPCI, and the occurrence of VF before or during PPCI was associated with increased 30-day mortality but not with long-term mortality. |
10,551 | Early repolarization of surface ECG predicts fatal ventricular arrhythmias in patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy and symptomatic ventricular arrhythmias. | The clinical characteristics and prognostic value of early repolarization (ER) in patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) and symptomatic ventricular arrhythmias remain unclear. We investigated the prevalence, clinical features, and cardiovascular outcomes of patients with symptomatic ARVD/C and ER.</AbstractText>A total of 59 consecutive ARVD/C patients hospitalized for catheter ablation, presenting with and without J-point elevations of ≥0.1mV in at least 2 inferior leads or lateral leads were enrolled. Clinical characteristics, electrophysiological study, substrate mapping, catheter ablation, and future clinical outcomes in a prospective patient registry were investigated.</AbstractText>ER was observed in 38 patients (64.4%). Among these patients, ER was found in the inferior leads in 18 patients (47.4%), in the lateral leads in 2 patients (5.3%), and in both inferior and lateral leads in 18 patients (47.4%). Patients exhibiting ER were commonly men, had lower right ventricular ejection fraction, had higher incidence of clinical ventricular fibrillation or aborted sudden cardiac death, had more defibrillator implantations, had higher the need of epicardial ablation, and had more major criteria according to the task force criteria. Significant higher incidence of induced ventricular fibrillation and shorter tachycardia cycle length of induced ventricular tachycardia were found during procedure. The recurrence rate of ventricular arrhythmias did not differ between patients with and without ER after catheter ablation.</AbstractText>A high prevalence of electrocardiographic ER was found among symptomatic ARVD/C patients undergoing catheter ablation. ER in 12-lead ECG is associated with an increased risk of clinical fatal ventricular arrhythmias.</AbstractText>Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
10,552 | Failure to deliver a shock in a dual-chamber implantable cardioverter-defibrillator: a case report. | Inappropriate implantable cardioverter-defibrillator (ICD) therapies due to supraventricular tachyarrhythmia (SVT) are a common problem. The authors report this case to warn of a possible detection problem and subsequent failure of deliver appropriate therapy in patients with atrial fibrillation (AF) and a dual-chamber ICD using the PARAD+ algorithm. To our knowledge this is the first reported case of failure to deliver a shock in a dual-chamber ICD due to the PARAD+ algorithm.</AbstractText>The authors present a case of a 68-year-old Caucasian man with permanent AF and a dual-chamber Sorin Paradym ICD with the PARAD+ algorithm, who presented an episode of sustained ventricular tachycardia (VT). The ICD did not store the event and did not delivery a therapy, although the heart rate curve was consistent with an episode of VT. No evidence of system dysfunction was found.</AbstractText>Due to simultaneous occurrence of VT and AF rhythms and alternation in rhythm classification by the PARAD+ algorithm the number of cycles needed to diagnose VT was not achieved and no therapy was delivered. In patients with permanent or long-term persistent AF with a dual-chamber ICD using the PARAD+ algorithm, discrimination should be based only on the ventricular channel. In patients with paroxysmal or persistent recurrent AF the risk of not delivering VT therapy must be weighed against the risk of inappropriate therapy.</AbstractText>Copyright © 2013 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.</CopyrightInformation> |
10,553 | Natural history of Brugada syndrome in a patient with congenital heart disease. | Risk stratification of sudden death in patients with Brugada syndrome (BrS) is a controversial issue, and there is currently no consensus on the best method. Examination of data from the natural history of the disease is of fundamental importance and may help to identify relatives at risk. At the same time, study of the genetic mutations responsible for the disease may also contribute to risk stratification of the syndrome, enabling identification of asymptomatic relatives carrying mutations. This paper presents the case of a young man, aged 26, monitored as a pediatric cardiology outpatient from birth for a simple structural heart defect not requiring surgery. Analysis of the evolution of the patient's electrocardiogram revealed the appearance, at the age of 20, of a pattern compatible with type I BrS. Following an episode of syncope and induction of polymorphic ventricular tachycardia in the electrophysiological study, a cardioverter-defibrillator was implanted. One year later, a single shock terminated an episode of ventricular fibrillation. A molecular study of the SCN5A gene identified a rare mutation, c.3622G>T (p.Glu1208X), recently described and associated with more severe phenotypes in patients with BrS, as in the case presented. |
10,554 | Participation in cardiac rehabilitation after hospitalisation for heart failure: a report from the BIO-HF registry. | Participation in cardiac rehabilitation (CR) after hospitalisation for heart failure (HF) is estimated to below, but specific data for Belgium are lacking. Therefore, we wanted to evaluate attendance after HF hospitalisation compared to patients after cardiac surgery or acute coronary syndrome (ACS). Moreover, the improvement in exercise capacity was compared with the other patient groups.</AbstractText>Patients who were hospitalized for HF (n=428), cardiac surgery (n=358) or ACS (n=467) in a single hospital, were prospectively included between January 2010 and May 2012. After hospitalisation for HF only 9% participated, compared to 29% after ACS and 56% after cardiac surgery. Non-participants in HF were older, more frequently women (P <0.01) and had a better left ventricular ejection fraction (P < 0.05). In addition, they had more frequently atrial fibrillation and problems to walk independently (P <0.01). At the start of the CR, HF patients had a worse clinical status and exercise capacity than patients after cardiac surgery or ACS (all P <0.001). However, exercise training resulted in a significant improvement in each group separately (all P < 0.001) and the relative improvement in exercise capacity in HF was comparable with the other groups.</AbstractText>Only 9% of HF patients participated in CR after hospitalisation. Age, female gender, a relatively well-preserved ventricular function and atrial fibrillation seem to impede attendance to CR. However, HF patients can have as much improvement in exercise capacity as other patient populations, suggesting that more effort is needed to increase participation in CR among HF patients.</AbstractText> |
10,555 | The Use of Automated External Defibrillators in Infants: A Report From the American Red Cross Scientific Advisory Council. | Automated external defibrillators (AEDs) have been used successfully in many populations to improve survival for out-of-hospital cardiac arrest. While ventricular fibrillation and pulseless ventricular tachycardia are more prevalent in adults, these arrhythmias do occur in infants. The Scientific Advisory Council of the American Red Cross reviewed the literature on the use of AEDs in infants in order to make recommendations on use in the population.</AbstractText>The Cochrane library and PubMed were searched for studies that included AEDs in infants, any external defibrillation in infants, and simulation studies of algorithms used by AEDs on pediatric arrhythmias.</AbstractText>There were 4 studies on the accuracy of AEDs in recognizing pediatric arrhythmias. Case reports (n = 2) demonstrated successful use of AED in infants, and a retrospective review (n = 1) of pediatric pads for AEDs included infants. Six studies addressed defibrillation dosages used. The algorithms used by AEDs had high sensitivity and specificity for pediatric arrhythmias and very rarely recommended a shock inappropriately. The energy doses delivered by AEDs were high, although in the range that have been used in out-of-hospital arrest. In addition, there are data to suggest that 2 to 4 J/kg may not be effective defibrillation doses for many children.</AbstractText>In the absence of prompt defibrillation for ventricular fibrillation or pulseless ventricular tachycardia, survival is unlikely. Automated external defibrillators should be used in infants with suspected cardiac arrest, if a manual defibrillator with a trained rescuer is not immediately available. Automated external defibrillators that attenuate the energy dose (eg, via application of pediatric pads) are recommended for infants. If an AED with pediatric pads is not available, the AED with adult pads should be used.</AbstractText> |
10,556 | Fibromuscular Dysplasia Leading to Spontaneous Coronary Artery Dissection with Sudden Cardiac Arrest. | A 30-year-old previously healthy female, who was six-week postpartum, experienced sudden collapse and tonic-clonic seizure. Emergency medicine services arrived at the scene and the patient was found to be in ventricular fibrillation. Advanced cardiovascular life support (ACLS) was initiated with return of spontaneous circulation. Afterwards, her initial EKG showed atrial fibrillation with rapid ventricular rate, ST elevation in leads II, III, and aVF, and ST depression in V2-V4. She was transferred to a tertiary care hospital where emergent angiogram was performed revealing obstruction of blood flow in the proximal and mid right coronary artery (RCA). A hazy and irregularly contoured appearance of the RCA was consistent with diagnosis of fibromuscular dysplasia. Subsequently, intravascular ultrasonogram (IVUS) was performed which confirmed the diagnosis of RCA dissection. Successful revascularization of the RCA was performed using two bare mental stents. After a complicated course in hospital, she was discharged in stable condition and did very well overall. |
10,557 | Nifekalant Versus Amiodarone in the Treatment of Cardiac Arrest: an Experimental Study in a Swine Model of Prolonged Ventricular Fibrillation. | The purpose of the experiment was to compare the effects of nifekalant and amiodarone on the return of spontaneous circulation (ROSC), survival, as well as on the hemodynamic parameters in a swine model of prolonged ventricular fibrillation (VF).</AbstractText>After 8 min of untreated VF, bolus doses of epinephrine (adrenaline) and either nifekalant, or amiodarone, or saline (n = 10 per group), were administered after randomization. Cardiopulmonary resuscitation (CPR) was commenced immediately after drug administration and defibrillation was attempted 2 min later. CPR was resumed for another 2 min after each defibrillation attempt and the same dose of adrenaline was given every 4th minute during CPR.</AbstractText>Forty-eight hour survival was significantly higher with nifekalant compared to amiodarone (p < 0.001) and saline (p = 0.02), (9/10 vs. 0/10 vs. 3/10, respectively). Systolic aortic pressure, diastolic aortic pressure and coronary perfusion pressure were significantly higher with nifekalant during CPR and immediate post-resuscitation period (p < 0.05). The animals in the amiodarone group had a slower heart rate at the 1st and 45th min post-ROSC (p < 0.001 and p = 0.006, respectively). The number of electric shocks required for terminating VF, time to ROSC and adrenaline dose were significantly higher with amiodarone compared to nifekalant (p < 0.001).</AbstractText>Nifekalant showed a more favorable hemodynamic profile and improved survival compared to amiodarone and saline in this swine model.</AbstractText> |
10,558 | Clinical Profile of Patients With High-Risk Tako-Tsubo Cardiomyopathy. | Although tako-tsubo cardiomyopathy (TTC) is regarded as a reversible condition with favorable outcome, a malignant clinical course evolves in some subjects. In this single-institution experience, we describe the clinical profile of patients with adverse TTC outcome. A cohort of 249 consecutive patients with TTC was interrogated for those with acute unstable presentation during the first 24 hours. Forty-seven patients (19%) experienced early complicated clinical course with cardiac arrest in 9 (ventricular fibrillation, n = 4, pulseless electrical activity, n = 3, and asystole, n = 2) or marked hypotension in 38 (systolic blood pressure ≤90 mm Hg requiring vasopressors and/or balloon pump). Of the 47 patients, Killip class III to IV heart failure was present in 30 (64%). Despite treatment, 8 patients (3%; all women) died inhospital due to respiratory failure, cardiogenic shock, or anoxic brain injury. All 8 inhospital deaths occurred among the 47 patients with unstable presentation, including 2 after cardiac arrest and 6 with marked hypotension. Post-TTC event mortality for a period of 4.7 ± 3.4 years significantly exceeded that in a matched general US population (standardized mortality ratio 1.4; 95% confidence interval 1.1 to 1.9; p = 0.005) largely due to noncardiac co-morbidities. In conclusion, contrary to widespread perception, TTC is not an entirely benign and reversible condition. Among this large cohort, a high-risk subgroup was identified with cardiac arrest or hemodynamic instability, accounting for all hospital deaths. Hospital nonsurvivors had a variety of irreversible co-morbid conditions with the potential to compromise clinical status and adversely affect short-term survival. Long-term survival after hospital discharge was also reduced compared with the general population because of noncardiac co-morbidities. |
10,559 | Gender and survival after sudden cardiac arrest: A systematic review and meta-analysis. | Conflicting results exist regarding the impact of gender on early survival after sudden cardiac arrest (SCA). We aimed to assess the association between female gender and early SCA survival.</AbstractText>We searched Embase, MEDLINE, EBM Reviews, Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews (between 1948 and January 2014) for studies evaluating the association between gender and survival after SCA. Two independent reviewers selected studies of any design or language. Pooled odds-ratios (OR) and 95% confidence intervals (CIs) were estimated using a random-effects model. Additional sensitivity analyses and meta-regression were carried out to explore heterogeneity.</AbstractText>Thirteen studies were included involving 409,323 patients. Women were more likely to present with SCA at home, less likely to have witnessed SCA, had a lower frequency of initial shockable rhythm but were more likely to receive bystander CPR. After adjustment for these differences, women were more likely to survive at hospital discharge (OR 1.1, 95% CI 1.03-1.20, p=0.006, I(2)=61%). This association persisted in multiple sensitivity analyses.</AbstractText>This meta-analysis of observational studies demonstrates that women have increased odds of survival after SCA. Further studies are needed to address mechanisms explaining this discrepancy.</AbstractText>Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
10,560 | A Practical Approach to the Investigation of an rSr' Pattern in Leads V1-V2. | The differential diagnosis of an rSr' pattern in leads V1-V2 on electrocardiogram is a frequently encountered entity in clinical cardiology. This finding often presents itself in asymptomatic and healthy individuals. The causes might vary from benign and nonpathological, to severe and life-threatening diseases, such as Brugada syndrome or arrhythmogenic right ventricular dysplasia. Workup of these patients involves a history and physical examination to screen for underlying cardiac disease and potential triggers. Routine investigation involves blood work and a thorough electrocardiographic examination. Echocardiography has a role in evaluating patients in whom structural heart disease is suspected. Pulmonary testing using computed tomography can be conducted if right ventricular enlargement is identified. More advanced testing is not warranted if these initial investigations are reassuring. Referral to an arrhythmia specialist should be considered for patients in whom this finding is due to Brugada syndrome, arrhythmogenic right ventricular dysplasia, or Wolf-Parkinson-White syndrome. We propose a clinical and electrocardiographic algorithm that will assist clinicians in narrowing their differential diagnosis. |
10,561 | Accessory papillary muscles and papillary muscle hypertrophy are associated with sudden cardiac arrest of unknown cause. | The present study was performed for elucidating the associations between the morphology of the papillary muscles (PMs) and sudden cardiac arrest (SCA).</AbstractText>We retrospectively reviewed history, laboratory data, electrocardiography, echocardiography, coronary angiography, and cardiac CT/MRI for 190 patients with SCA. The prevalence of accessory PMs and PM hypertrophy in patients with SCA of unknown cause was compared with that in patients with SCA of known causes and 98 age- and sex-matched patients without SCA. An accessory PM was defined as a PM with origins separated from the anterolateral and posteromedial PMs, or a PM that branched into two or three bellies at the base of the anterolateral or posteromedial PM. PM hypertrophy was defined as at least one of the two PMs having a diameter of ≥1.1cm.</AbstractText>In 49 patients (age 49.9±15.9years; 38 men) the cause of SCA was unknown, whereas 141 (age 54.2±16.6years; 121 men) had a known cause. The prevalence of accessory PMs was significantly higher in the unknown-cause group than in the known-cause group (24.5% and 7.8%, respectively; p=0.002) or the no-SCA group (7.1%, p=0.003). The same was true for PM hypertrophy (unknown-cause 12.2%, known-cause 2.1%, p=0.010; no SCA group 1.0%, p=0.006). By logistic regression, accessory PM and PM hypertrophy were independently associated with sudden cardiac arrest of unknown cause.</AbstractText>An accessory PM and PM hypertrophy are associated with SCA of unknown cause.</AbstractText>Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
10,562 | Cardioprotective effect of Thymoquinone: A constituent of Nigella sativa L., against myocardial ischemia/reperfusion injury and ventricular arrhythmias in anaesthetized rats. | Reperfusion of the ischemic myocardium causes the myocardial injury and life-threatening ventricular arrhythmias in human. This study aimed to investigate the effects of thymoquinone (TQ) on myocardial ischemia/reperfusion (I/R) injury and ischemia- and reperfusion-induced ventricular arrhythmias in anaesthetized rats. Adult male Wistar albino rats were divided into two groups, each containing a control and TQ-treated subgroups. In group I, the myocardial infarct size was determined by triphenyl tetrazolium chloride staining following 2-h reperfusion preceded by 30 min of ischemia. In group II, a 6-min myocardial ischemia was followed by a 10-min reperfusion. TQ-treated subgroups were treated with TQ (10 mg/100 μl/kg, i.p.) and the control subgroups were treated with the vehicle (100 μl/kg, i.p.) 20 min prior to the ischemic period. Ischemia was induced by ligating the left main coronary artery, followed by reperfusion. TQ treatment reduced the infarct size (15 ± 4% versus 69 ± 6%, P<0.01). Pretreatment with TQ decreased arrhythmia scores, as well as the incidence of ventricular tachycardia and the incidence of ventricular fibrillation during the reperfusion period (arrhythmia scores: 1.4 ± 0.3 versus 4.4 ± 0.3, P<0.01). These results suggest that TQ confers protection against myocardial I/R injury and suppresses reperfusion-induced arrhythmias. |
10,563 | Association between ventricular pacing and persistent atrial fibrillation in patients indicated to elective pacemaker replacement: Results of the Prefer for Elective Replacement MVP (PreFER MVP) randomized study. | Pacing in the right ventricle can cause a variety of detrimental effects, including atrial tachyarrhythmias (atrial tachycardia [AT]/atrial fibrillation [AF]).</AbstractText>The purpose of this study was to evaluate the incidence and predictors of persistent AT/AF in patients with long-term exposure to ventricular pacing.</AbstractText>In a multicenter international trial, 605 patients (age 75 ± 11 years, 240 women) referred for replacement of an implanted pacemaker or implantable cardioverter-defibrillator (ICD), with a history of high-percentage (>40%) ventricular pacing, were randomly allocated to standard dual-chamber pacing or managed ventricular pacing (MVP), a pacing modality that minimizes ventricular pacing. The main end-point of this secondary analysis of the PreFER MVP randomized study was persistent AT/AF, defined as ≥7 consecutive days with AT/AF or AT/AF interrupted by atrial cardioversion or AT/AF present during 2 consecutive follow-up visits.</AbstractText>Persistent AT/AF was observed in 71 patients (11.7%) after 2 years of follow-up. At multivariable Cox regression analysis, prior AT/AF (hazard ratio [HR] 2.85, 95% confidence interval [CI] 1.20-6.22, P = .017) and ventricular pacing percentage, estimated in the first 3 months, ≥10% (HR 3.24, 95% 95% CI 1.13-9.31, P = .029) were independent predictors for persistent AT/AF. MVP was associated with persistent AT/AF risk (HR 3.41, 95% 95% CI 1.10-10.6, P = .024) in the subgroup of patients with baseline long PR interval (PR >230 ms) but not in the whole population.</AbstractText>In pacemaker and ICD replacement patients, a high percentage of ventricular pacing is associated with higher risk of persistent AT/AF. Use of algorithms that minimize right ventricular pacing may benefit patients with normal spontaneous AV conduction but should be evaluated with caution in patients with long PR interval.</AbstractText>Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
10,564 | Anomalous Left Coronary From the Pulmonary Artery Presenting as Ventricular Fibrillation After Persistent Ductus Arteriosus Ligation. | An anomalous left coronary artery from the pulmonary artery (ALCAPA) is rarely associated with persistent ductus arteriosus (PDA). A large PDA can maintain perfusion in the left coronary artery, delaying presentation. Assessing the origin of the coronary arteries before PDA ligation is difficult, often being performed in very small or even preterm babies. We present the case of a 5-month-old infant with echocardiographic features of mitral regurgitation and subendocardial ischemia who experienced ischemia and cardiac arrest after PDA ligation. Transesophageal echocardiography demonstrated ALCAPA, and left coronary translocation was performed. The infant was discharged after 10 days. |
10,565 | Impaired Global Right Ventricular Longitudinal Strain Predicts Long-Term Adverse Outcomes in Patients with Pulmonary Arterial Hypertension. | New 2-dimensional strain echocardiography enables quantification of right ventricular (RV) mechanics by assessing global longitudinal strain of RV (GLSRV) in patients with pulmonary arterial hypertension (PAH). However, the prognostic significance of impaired GLSRV is unclear in these patients.</AbstractText>Comprehensive echocardiography was performed in 51 consecutive PAH patients without atrial fibrillation (40 females, 48 ± 14 years old) with long-term follow-up. GLSRV was measured with off-line with velocity vector imaging (VVI, Siemens Medical System, Mountain View, CA, USA).</AbstractText>GLSRV showed significant correlation with RV fractional area change (r = -0.606, p < 0.001), tricuspid annular plane systolic excursion (r = -0.579, p < 0.001), and RV Tei index (r = 0.590, p < 0.001). It showed significant correlations with pulmonary vascular resistance (r = 0.469, p = 0.001) and B-natriuretic peptide concentration (r = 0.351, p = 0.012). During a clinical followup time (45 ± 15 months), 20 patients experienced one or more adverse events (12 death, 2 lung transplantation, and 15 heart failure hospitalization). After multivariate analysis, age [hazard ratio (HR) = 2.343, p = 0.040] and GLSRV (HR = 2.122, p = 0.040) were associated with adverse clinical events. Age (HR = 3.200, p = 0.016) and GLSRV (HR = 2.090, p = 0.042) were also significant predictors of death. Impaired GLSRV (≥ -15.5%) was associated with lower event-free survival (HR = 4.906, p = 0.001) and increased mortality (HR = 8.842, p = 0.005).</AbstractText>GLSRV by VVI showed significant correlations with conventional echocardiographic parameters indicating RV systolic function. Lower GLSRV (≥ -15.5%) was significantly associated with presence of adverse clinical events and deaths in PAH patients.</AbstractText> |
10,566 | Left Ventricular Strain as Predictor of Chronic Aortic Regurgitation. | It is not well known about the implication of left ventricular (LV) strain as a predictor for mortality in patients with chronic aortic regurgitation (AR). The purpose of this study was to investigate whether global longitudinal strain measured by two-dimensional speckle-tracking echocardiography could predict long-term outcome in patients with chronic AR.</AbstractText>This is a single center non-randomized retrospective observational study. The patients with chronic AR from January 2002 to December 2012 were retrospectively enrolled. Following patients were excluded; combined other significant valvular disease, previous heart surgery, aortic disease, congenital heart disease, acute AR and young age under 18 years old. Finally, 60 patients were analyzed and the LV global strain rate was measured on apical four chamber image (GS-4CH).</AbstractText>During 64 months follow-up duration, 16 patients (26.7%) were deceased and 38 patients (63.3%) underwent aortic valve replacement (AVR). Deceased group was older (69 years old vs. 51 years old, p < 0.001) and had lower longitudinal strain (-12.05 ± 3.72% vs. -15.66 ± 4.35%, p = 0.005). Kaplan-Meier survival curve stratified by GS-4CH showed a trend of different event rate (log rank p = 0.001). On multivariate analysis by cox proportional hazard model adjusting for age, sex, body surface area, history of atrial fibrillation, blood urea nitrogen, LV dilatation, LV ejection fraction and AVR, decreased GS-4CH proved to be an independent predictor of mortality in patients with chronic AR (hazard ratio 1.313, 95% confidence interval 1.010-1.706, p = 0.042).</AbstractText>GS-4CH may be a useful predictor of mortality in patient with chronic AR.</AbstractText> |
10,567 | Pulmonary edema following transcatheter closure of atrial septal defect. | We describe an incident of development of acute pulmonary edema after the device closure of a secundum atrial septal defect in a 52-year-old lady, which was treated with inotropes, diuretics and artificial ventilation. Possibility of acute left ventricular dysfunction should be considered after the defect closure in the middle-aged patients as the left ventricular compliance may be reduced due to increased elastic stiffness and diastolic dysfunction. Baseline left atrial pressure may be > 10 mmHg in these patients. Associated risk factors for the left ventricular dysfunction are a large Qp:Qs ratio, systemic hypertension, severe pulmonary hypertension and paroxysmal atrial fibrillation. |
10,568 | The natural history of atrial fibrillation in patients with permanent pacemakers: is atrial fibrillation a progressive disease? | Atrial fibrillation (AF) is thought to be a progressive arrhythmia, starting with short paroxysmal episodes, until eventually, it becomes permanent. Evidence for this is limited to studies with short follow-up or with minimal cardiac rhythm monitoring. We utilised the continuous rhythm monitoring capabilities of implanted pacemakers to define better the natural history of AF.</AbstractText>The study included 356 patients with pacemaker devices capable of continuous atrial rhythm monitoring (186 male, mean age (± SD) 79.5 ± 8.9 years). All clinical records, including history/physical examination reports, laboratory results, ECGs and Holter monitoring data were reviewed. Patients were included if AF episodes >30 s were documented. Permanent pacemaker diagnostic data were reviewed at least every 12 months. ACC/AHA/ESC guidelines were used to define AF episodes as paroxysmal, persistent or long-standing persistent/permanent.</AbstractText>Study follow-up period (± SD) was 7.2 ± 3.1 years. Over the study period, 179 of 356 patients (50.3 %) had at least one episode of persistent AF. Of the 356 patients, 314 (88.2 %) had paroxysmal AF and 42 (11.8 %) had persistent AF at the time of diagnosis. The predominant AF subtype, at latest follow-up, was paroxysmal for 192 patients (53.9 %), persistent for 77 (21.6 %) and long-standing persistent/permanent for 87 (24.4 %). Univariable predictors of progression to persistent AF were (1) male gender, (2) increasing left atrial diameter (LAD), (3) reduced atrial pacing (AP) and (4) increasing ventricular pacing.</AbstractText>Although many patients with AF will have persistent episodes, long-term continuous pacemaker follow-up demonstrates that the majority will have a paroxysmal, as opposed to persistent, form of the arrhythmia.</AbstractText> |
10,569 | Phenotypic expression is a prerequisite for malignant arrhythmic events and sudden cardiac death in arrhythmogenic right ventricular cardiomyopathy. | Whether a desmosomal (DS)-gene defect may in itself induce life-threatening ventricular arrhythmias regardless of phenotypic expression of arrhythmogenic right ventricular cardiomyopathy (ARVC) is still debated. This prospective study evaluated the long-term outcome of DS-gene mutation carriers in relation to the ARVC phenotypic expression.</AbstractText>The study population included 116 DS-gene mutation carriers [49% males; median age 33 years (16-48 years)] without prior sustained ventricular tachycardia (VT) or ventricular fibrillation (VF). The incidence of the arrhythmic endpoint, including sudden cardiac death (SCD), aborted SCD, sustained VT, and appropriate implantable cardioverter-defibrillator (ICD) intervention was evaluated prospectively and stratified by the presence of ARVC phenotype and risk factors (syncope, ventricular dysfunction, and non-sustained VT). At enrolment, 40 of 116 (34%) subjects fulfilled the criteria for definite ARVC while the remaining were either borderline or phenotype negatives. During a median follow-up of 8.5 (5-12) years, 10 patients (9%) had arrhythmic events (0.9%/year). The event rate was 2.3%/year among patients with definite ARVC and 0.2%/year among borderline or phenotype negative patients (P = 0.002). In patients with definite ARVC, the incidence of arrhythmias was higher in those with ≥1 risk factors (4.1%/year) than in those with no risk factors (0.4%/year, P = 0.02). Mortality was 0.2%/year (1 heart failure death and 1 SCD).</AbstractText>The ARVC phenotypic expression is a prerequisite for the occurrence of life-threatening arrhythmias in DS-gene mutation carriers. The vast majority of malignant arrhythmic events occurred in patients with an overt disease phenotype and major risk factors suggesting that this subgroup most benefits from ICD therapy.</AbstractText>Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.</CopyrightInformation> |
10,570 | Ranolazine Attenuates the Electrophysiological Effects of Myocardial Stretch in Langendorff-Perfused Rabbit Hearts. | Mechanical stretch is an arrhythmogenic factor found in situations of cardiac overload or dyssynchronic contraction. Ranolazine is an antianginal agent that inhibits the late Na (+) current and has been shown to exert a protective effect against arrhythmias. The present study aims to determine whether ranolazine modifies the electrophysiological responses induced by acute mechanical stretch.</AbstractText>The ventricular fibrillation modifications induced by acute stretch were studied in Langendorff-perfused rabbit hearts using epicardial multiple electrodes under control conditions (n = 9) or during perfusion of the late Na(+) current blocker ranolazine 5 μM (n = 9). Spectral and mapping techniques were used to establish the ventricular fibrillation dominant frequency, the spectral concentration and the complexity of myocardial activation in three situations: baseline, stretch and post-stretch.</AbstractText>Ranolazine attenuated the increase in ventricular fibrillation dominant frequency produced by stretch (23.0 vs 40.4 %) (control: baseline =13.6 ± 2.6 Hz, stretch = 19.1 ± 3.1 Hz, p < 0.0001; ranolazine: baseline =  1.4 ± 1.8 Hz, stretch =14.0 ± 2.4 Hz, p < 0.05 vs baseline, p < 0.001 vs control). During stretch, ventricular fibrillation was less complex in the ranolazine than in the control series, as evaluated by the lesser percentage of complex maps and the greater spectral concentration of ventricular fibrillation. These changes were associated to an increase in the fifth percentile of VV intervals during ventricular fibrillation (50 ± 8 vs 38 ± 5 ms, p <  .01) and in the wavelength of the activation (2.4 ± 0.3 vs 1.9 ± 0.2 cm, p < 0.001) under ranolazine.</AbstractText>The late inward Na(+) current inhibitor ranolazine attenuates the electrophysiological effects responsible for the acceleration and increase in complexity of ventricular fibrillation produced by myocardial stretch.</AbstractText> |
10,571 | The Effect of Direct Current Stimulation versus T-Wave Shock on Defibrillation Threshold Testing. | There are several methods to induce ventricular fibrillation (VF) during defibrillation threshold (DFT) testing. Delivering a shock at a critical time during the T wave (T-shock) is the conventional approach, while delivering a constant direct current voltage (DC stim) from the implantable cardioverter defibrillator is an alternative method. Only a few reports compare VF induction methods. The purpose of this study was to evaluate the effects and safety of DC stim versus T-shock.</AbstractText>We retrospectively investigated 414 consecutive patients undergoing DFT testing. We compared the two groups (DC stim and T-shock) with respect to clinical characteristics, electrocardiogram (ECG) changes, and complications.</AbstractText>Ventricular arrhythmia, including ventricular tachycardia (VT) and VF, was induced by DC stim in 93 patients or T-shock in 321 patients. No more than three attempts were performed during one procedure. There was no significant difference in the baseline ECG, induced tachycardia cycle length (TCL), or complications between the two groups. However, the induced TCL was significantly shorter than the clinical TCL regardless of induction method (P = 0.001). Five patients suffered major complications (i.e., electromechanical dissociation or incessant VT). A history of atrial fibrillation was significantly greater in patients with major complications than the others (80% vs 24%, P = 0.004), and was an independent predictor on multivariate analysis.</AbstractText>There is no significant difference in induced TCL or complications between the DC stim and T-shock. The induced TCL is significantly shorter than clinical TCL regardless of induction method.</AbstractText>© 2015 Wiley Periodicals, Inc.</CopyrightInformation> |
10,572 | Thyroid Storm with Heart Failure Treated with a Short-acting Beta-adrenoreceptor Blocker, Landiolol Hydrochloride. | Beta-adrenoreceptor blockers are essential in controlling the peripheral actions of thyroid hormones and a rapid heart rate in patients with thyroid storm, although they should be used with great caution when there is the potential for heart failure. A 67-year-old woman was diagnosed as having thyroid storm in addition to marked tachycardia with atrial fibrillation and heart failure associated with a reduced left ventricular function. The administration of an oral beta blocker, bisoprolol fumarate, induced hypotension and was not tolerable for the patient, whereas landiolol hydrochloride, a short-acting intravenous beta-adrenoreceptor blocker with high cardioselectivity and a short elimination half-life, was useful for controlling the patient's tachycardia and heart failure without causing hemodynamic deterioration. |
10,573 | Long-term Prognosis of Paroxysmal Atrial Fibrillation and Predictors for Progression to Persistnt or Chronic Atrial Fibrillation in the Korean Population. | Little is known about the long-term prognosis of or predictors for the different clinical types of atrial fibrillation (AF) in Korean populations. The aim of this study was to validate a risk stratification to assess the probability of AF progression from paroxysmal AF (PAF) to persistent AF (PeAF) or permanent AF. A total of 434 patients with PAF were consecutively enrolled (mean age; 71.7 ± 10.7 yr, 60.6% male). PeAF was defined as episodes that are sustained > 7 days and not self-terminating, while permanent AF was defined as an ongoing long-term episode. Atrial arrhythmia during follow-up was defined as atrial premature complex, atrial tachycardia, and atrial flutter. During a mean follow-up of 72.7 ± 58.3 months, 168 patients (38.7%) with PAF progressed to PeAF or permanent AF. The mean annual AF progression was 10.7% per year. In univariate analysis, age at diagnosis, body mass index, atrial arrhythmia during follow-up, left ventricular ejection fraction, concentric left ventricular hypertrophy, left atrial diameter (LAD), and severe mitral regurgitation (MR) were significantly associated with AF progression. In multivariate analysis, age at diagnosis (P = 0.009), atrial arrhythmia during follow-up (P = 0.015), LAD (P = 0.002) and MR grade (P = 0.026) were independent risk factors for AF progression. Patients with younger age at diagnosis, atrial arrhythmia during follow-up, larger left atrial chamber size, and severe MR grade are more likely to progress to PeAF or permanent AF, suggesting more intensive medical therapy with close clinical follow-up would be required in those patients. |
10,574 | Relationship between diastolic ventricular dysfunction and subclinical sleep-disordered breathing in atrial fibrillation ablation candidates. | Sleep-disordered breathing (SDB) is recognized as a primary factor or mediator of atrial fibrillation (AF). We hypothesized that the severity of SDB among AF ablation candidates would be associated with left ventricular diastolic dysfunction (LVDD) even for subclinical SDB. A total of 246 patients hospitalized for initial pulmonary vein isolation (PVI) were analyzed. Known SDB cases were excluded. We measured the oxygen desaturation index (ODI) by pulse oximetry overnight as an indicator of SDB, and classified SDB severity by 3 % ODI as normal (ODI < 5 events/h), mild (ODI ≤ 5 to <15 events/h), or moderate-to-severe (ODI ≥15 events/h). The LVDD was assessed by echocardiography using combined categories with tissue Doppler imaging and left atrial (LA) volume measurement. Among the participants, 42 patients (17.1 %) had LVDD. The prevalence of LVDD increased with the SDB severity from 8.6 % (normal) to 12.7 % (mild) to 40.0 % (moderate-to-severe SDB) (p < 0.0001). In the multivariate logistic regression analysis, the odds ratio of having LVDD in the moderate-to-severe SDB group (ODI ≥ 15) vs. normal group (ODI < 5) was 5.96 (95 % CI, 2.10-19.00, P = 0.006). The presence of moderate-to-severe SDB in AF ablation candidates adversely affected LV diastolic function even during a subclinical state of SDB. |
10,575 | Clinical Study Regarding Arrhythmogenic Risk Factors and Oxidative Stress Inductibility in Young People. | Rhythm disorders in young people are often reported and when they are persistent, repetitive or with a severity degree, an ethiopathgenical assessment of arrhythmogenic risk factors and their implications is required.</AbstractText>Arrhythmogenic risk factors evaluation and the possibility of determining oxidative stress in the arrhythmic pathology in young people.</AbstractText>The study was conducted on 184 young subjects, aged 16-26 years old; the points of interest were: the presence or absence of cardiac dysrhythmias, the existence of proarrhythmogenic risk factors and determination of oxidative stress status modifications.</AbstractText>Of the studied young subjects, 39% presented heart rhythm disturbances, repetitive or persistent (atrial extrasystolic arrhythmia, sinus tachycardia, ventricular extrasystolic arrhythmia, paroxysmal atrial fibrillation, paroxysmal supraventricular tachycardia, associated dysrhythmias, atrial flutter, sinus bradycardia), which have been associated with the following risk factors: coffee consumption 82%, stress 80%, physical effort 72%, energy drinks consumption 72%, hyperlipidic diet 69%, familial predisposition 69%, alcohol intake 53%, frequent sleep deprivation 50%, smoking 31%, overweight 31%. The observed risk factors may be involved in the increasing of oxidative stress level, and, for this reason, the determination of oxidative stress biomarkers is required. The association of arrhythmogenic risk factors, with the expression of oxidative stress markers and the existence of enzymatic genetic polymorphism of redox systems, requires proper monitoring for the further risk of endothelial lesions induction, leading to aterosclerosis.</AbstractText>Arrhythmogenic risk factors and biomarkers of oxidative stress are important, especially in young people cases, for monitoring the cardiovascular risk, for primary prevention and early treatment.</AbstractText> |
10,576 | The Diagnosis and Clinical Implications of Interatrial Block. | Impaired interatrial conduction or interatrial block is now well-documented but is not described as an individual electrocardiographic (ECG) pattern in the majority of ECG literature. In fact the term <i>atrial abnormality</i> has been adopted to encompass both left atrial enlargement (LAE) and interatrial block. In this paper, we maintain that interatrial blocks and atrial enlargement are separate entities, and that interatrial blocks, similar to other types of blocks at sinoatrial, AV junctional, and ventricular level, exhibit a specific ECG pattern that may present first, second, and third degree types of conduction block. The third degree or advanced interatrial block (A-IAB) is frequently associated with atrial fibrillation/atrial flutter (AF/AFl), and constitutes a true newly-described syndrome. |
10,577 | A Comparative Study of Early Afterdepolarization-Mediated Fibrillation in Two Mathematical Models for Human Ventricular Cells. | Early afterdepolarizations (EADs), which are abnormal oscillations of the membrane potential at the plateau phase of an action potential, are implicated in the development of cardiac arrhythmias like Torsade de Pointes. We carry out extensive numerical simulations of the TP06 and ORd mathematical models for human ventricular cells with EADs. We investigate the different regimes in both these models, namely, the parameter regimes where they exhibit (1) a normal action potential (AP) with no EADs, (2) an AP with EADs, and (3) an AP with EADs that does not go back to the resting potential. We also study the dependence of EADs on the rate of at which we pace a cell, with the specific goal of elucidating EADs that are induced by slow or fast rate pacing. In our simulations in two- and three-dimensional domains, in the presence of EADs, we find the following wave types: (A) waves driven by the fast sodium current and the L-type calcium current (Na-Ca-mediated waves); (B) waves driven only by the L-type calcium current (Ca-mediated waves); (C) phase waves, which are pseudo-travelling waves. Furthermore, we compare the wave patterns of the various wave-types (Na-Ca-mediated, Ca-mediated, and phase waves) in both these models. We find that the two models produce qualitatively similar results in terms of exhibiting Na-Ca-mediated wave patterns that are more chaotic than those for the Ca-mediated and phase waves. However, there are quantitative differences in the wave patterns of each wave type. The Na-Ca-mediated waves in the ORd model show short-lived spirals but the TP06 model does not. The TP06 model supports more Ca-mediated spirals than those in the ORd model, and the TP06 model exhibits more phase-wave patterns than does the ORd model. |
10,578 | Safety of symptom-limited exercise testing in a big cohort of a modern ICD population. | Exercise may predispose to ventricular arrhythmias especially in patients with congestive heart failure. As therapy with implanted cardioverter-defibrillators (ICDs) has become standard medical care, there is an emerging number of exercise tests that need to be performed in patients with ICDs. In contrast, little is known about the safety of symptom-limited exercise testing in these patients.</AbstractText>400 ICD patients performed symptom-limited exercise treadmill testing. 200 patients performed a ramp protocol with an initial workload of 0 W increased by 15 W every minute. Another 200 ICD patients did a slightly modified ramp protocol with again an initial workload of 0 W but with an increased capacity of 15 W every 2 min. The study population consists mainly of patients with ischemic (63%) and non-ischemic (34%) heart disease. Atrial fibrillation was present in 16% of the subjects. The mean ejection fraction was 28 ± 8, and 78% of the patients had an ejection fraction below 30%. In this cohort of patients, no sustained ventricular arrhythmias and no deaths occurred during or after exercise testing. No inappropriate shock delivery was observed. The modified ramp protocol resulted in a prolonged exercise time with equal exercise capacity but does not result in an enhanced susceptibility for ventricular arrhythmias.</AbstractText>Symptom-limited exercise treadmill testing in heart failure patients with ICDs is a safe procedure. The use of a ramp protocol is sufficient in terms of safety and is easy to perform in general practice. The exercise duration in heart failure patients with ICDs does not predict serious adverse events.</AbstractText> |
10,579 | [Dyspnea in left-sided heart disease]. | Shortness of breath (dyspnea) is a common symptom in left-sided heart disease but clinically, patient symptoms show a high variability. Echocardiography is the mainstay for evaluating whether left-sided heart disease is the cause of dyspnea. If left-sided heart failure is diagnosed, this symptom complex must then be subjected to further etiological evaluation. Hypertensive, ischemic and valvular heart diseases are common, as well as atrial fibrillation. If the patient does not have angina pectoris, testing for ischemic heart disease should be done non-invasively by coronary computed tomography or testing for regional myocardial ischemia. Coronary revascularization is indicated only when a prognostically relevant ischemia of more than 10 % of the left ventricle is diagnosed. Diuretics are important for the relief of dyspnea but do not improve the prognosis of patients. In patients with reduced left ventricular function, combination therapy with angiotensin-converting enzyme (ACE) inhibitors, beta blockers and aldosterone antagonists improve the symptoms and prognosis. For treatment of heart failure with preserved ejection fraction evidence-based measures are still lacking. In this case the recommended therapy consists of optimal treatment of comorbidities, regulation of heart rate and blood pressure and participation in structured exercise programs. Angiotensin receptor blockers and aldosterone antagonists can be given in patients with more severe symptoms even though the available data are very sparse. |
10,580 | Anticoagulation in Heart Failure: a Review. | Heart failure (HF) with reduced left ventricular function inflicts a large and growing burden of morbidity and mortality in the US and across the globe. One source of this burden is stroke. While it appears that HF itself may impose some risk of stroke, it is in the presence of other risk factors, like atrial fibrillation, that the greatest risks are observed. Therapeutic anticoagulation is the mainstay of risk reduction strategies in this population. While warfarin was the only available therapy for anticoagulation for many decades, there are now four direct oral anticoagulants available. In three of these four, outcomes in the specific subgroup of patients with heart failure have been examined. In this review, we provide some pathophysiologic basis for the risk of stroke in heart failure. In addition, the available therapeutic options for stroke risk prevention in heart failure are described in detail including how these options are incorporated into relevant professional society guidelines. |
10,581 | Cardiac Magnetic Resonance for Ventricular Arrhythmia Therapies in Patients with Coronary Artery Disease. | Cardiac magnetic resonance (CMR) imaging is currently gold standard for myocardial tissue characterization and scar assessment. CMR serves potential prognostic information in patients with coronary artery disease (CAD) for both ventricular arrhythmia risk, as well as it may also be used for guiding VT ablation procedures. This review is focused on the usefulness of CMR for ventricular arrhythmia therapies in patients with CAD. |
10,582 | Systolic and Diastolic Function by Tissue Doppler Imaging Predicts Mortality in Patients with Atrial Fibrillation. | Tissue Doppler Imaging (TDI) detects early signs of left ventricular dysfunction. The prognostic potential of TDI in patients with atrial fibrillation (AF) has, however, not yet been clarified. This study evaluates the prognostic value of TDI in patients with atrial fibrillation.</AbstractText>In total, echocardiograms from 313 patients with AF during examination were analyzed offline. Longitudinal systolic velocity (s'), early diastolic velocity (e') and longitudinal displacement (LD) were measured by color TDI. During a median follow-up of 891 days, 64 patients (20%) died. TDI was significantly associated with all-cause mortality, and the risk of dying increased significantly per 1 cm/s decrease in s' (HR of 1.31, 95% CI 1.05-1.63; p=0.018) and e' (HR of 1.17, 95% CI 1.01-1.35; p=0.038) respectively, even after adjustment for age, gender, heart rate, aortic stenosis, DM and LVEF quartiles. LD also proved to be a significant predictor of outcome after multivariate adjustment (HR 1.23; 95% CI 1.05-1.44; p=0.012). The population was stratified according to high or low s' and e'. Patients with low s' and e' had more than three times the risk of mortality compared to the patients with high s' and e' (HR 3.64; 95% CI 1.83-7.26; p<0.001) and remained in significantly higher risk after adjustment for various risk factors.</AbstractText>Both systolic and diastolic performance, as assessed by TDI, are strong predictors of mortality in patients with atrial fibrillation, and especially the combination of systolic and diastolic dysfunction is a significant prognostic marker.</AbstractText> |
10,583 | Late Sodium Current in Human Atrial Cardiomyocytes from Patients in Sinus Rhythm and Atrial Fibrillation. | Slowly inactivating Na+ channels conducting "late" Na+ current (INa,late) contribute to ventricular arrhythmogenesis under pathological conditions. INa,late was also reported to play a role in chronic atrial fibrillation (AF). The objective of this study was to investigate INa,late in human right atrial cardiomyocytes as a putative drug target for treatment of AF. To activate Na+ channels, cardiomyocytes from transgenic mice which exhibit INa,late (ΔKPQ), and right atrial cardiomyocytes from patients in sinus rhythm (SR) and AF were voltage clamped at room temperature by 250-ms long test pulses to -30 mV from a holding potential of -80 mV with a 100-ms pre-pulse to -110 mV (protocol I). INa,late at -30 mV was not discernible as deviation from the extrapolated straight line IV-curve between -110 mV and -80 mV in human atrial cells. Therefore, tetrodotoxin (TTX, 10 μM) was used to define persistent inward current after 250 ms at -30 mV as INa,late. TTX-sensitive current was 0.27±0.06 pA/pF in ventricular cardiomyocytes from ΔKPQ mice, and amounted to 0.04±0.01 pA/pF and 0.09±0.02 pA/pF in SR and AF human atrial cardiomyocytes, respectively. With protocol II (holding potential -120 mV, pre-pulse to -80 mV) TTX-sensitive INa,late was always larger than with protocol I. Ranolazine (30 μM) reduced INa,late by 0.02±0.02 pA/pF in SR and 0.09±0.02 pA/pF in AF cells. At physiological temperature (37°C), however, INa,late became insignificant. Plateau phase and upstroke velocity of action potentials (APs) recorded with sharp microelectrodes in intact human trabeculae were more sensitive to ranolazine in AF than in SR preparations. Sodium channel subunits expression measured with qPCR was high for SCN5A with no difference between SR and AF. Expression of SCN8A and SCN10A was low in general, and lower in AF than in SR. In conclusion, We confirm for the first time a TTX-sensitive current (INa,late) in right atrial cardiomyocytes from SR and AF patients at room temperature, but not at physiological temperature. While our study provides evidence for the presence of INa,late in human atria, the potential of such current as a target for the treatment of AF remains to be demonstrated. |
10,584 | Mutation Analysis of KCNQ1, KCNH2 and SCN5A Genes in Taiwanese Long QT Syndrome Patients. | Long QT syndrome (LQTS) is a genetic cardiac disease. Gene mutation affects the structure or function of ion channels that are associated with a high risk of sudden death. The goal of this study was to determine the frequency of KCNQ1, KCNH2, and SCN5A mutations in LQTS in a Taiwanese population. Genomic DNA was extracted from peripheral blood samples obtained from 5 patients with LQTS and the family members of 3 LQTS patients. High resolution melting (HRM) analysis and direct DNA sequencing were used to characterize the KCNQ1, KCNH2, and SCN5A genetic variations. HRM analysis was successfully optimized for 14 of the 16 exons of the KCNQ1, 5 of the 15 exons of the KCNH2, and 23 of the 27 exons of the SCN5A. HRM and direct DNA sequencing was applied to the cohort of 5 cases and some of their family. The genetic testing revealed two pathogenic mutations (p.T309I in KCNQ1 and p.R744fs in KCNH2) and all of the mutational frequencies in KCNQ1 and KCNH2 were 20%. In the two patients who carry the pathogenic mutation presenting with recurrent syncope due to ventricular fibrillation, an implantable cardioverter defibrillator was implanted. We also discovered 11 polymorphisms in KCNQ1, 3 in KCNH2, and 5 in SCN5A. Two-fifths of cases (40%) presented with one of the three major LQTS-causing gene mutations. |
10,585 | Right Bundle Branch Block-Like Pattern During Ventricular Pacing: A Surface Electrocardiographic Mapping Technique to Locate the Ventricular Lead. | In patients with paced rhythm, a right bundle branch block (RBBB)-like pattern may suggest inadvertent left ventricular (LV) lead placement. However, in most cases, the lead is indeed in the right ventricle as intended.</AbstractText>We performed a retrospective analysis of postimplantation electrocardiograms (ECGs) for the period 2000-2013 to determine the prevalence of a RBBB-like pattern. A 12-lead ECG was recorded in the standard position and with displacement of leads V1-V2 to the fifth and sixth intercostal spaces (ICSs), assessing the ability of this manoeuvre to unmask a concealed LBBB-like pattern. Patients with true LV pacing, both endocardial and epicardial, were used as controls (n = 10).</AbstractText>A total of 943 patients were analyzed. The prevalence of RBBB-like pattern was 8.1% (n = 77), and 26 patients were included in the study. Displacement of leads V1-V2 to the fifth ICS resulted in transition to a LBBB-like pattern with a QS wave in V1 in 14 of 26 patients (sensitivity, 53%; specificity, 100%), whereas displacement to the sixth ICS resulted in a QS pattern in all patients (sensitivity and specificity, 100%). In all patients in the control group, the ECG depicted a RBBB configuration with leads V1-V2 in the standard position, as well as at the fifth and sixth ICSs.</AbstractText>In patients with paced rhythm and a RBBB-like pattern on the 12-lead ECG, displacement of leads V1-V2 to the sixth ICS accurately identifies the presence of true right ventricular pacing.</AbstractText>Copyright © 2015 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
10,586 | [INDUCED HYPOTHERMIA AFTER CARDIAC ARREST]. | Sudden cardiac death in adults remains a challenge in cardiovascular medicine. Cardiac arrest often drives neurological damage resulting from cerebral hypoxia, causing a series of cellulose tissue alterations that lead to brain injury. Therapeutic hypothermia decreases oxygen demand acting as protection to the brain.</AbstractText>To describe the casuistry of hypothermia after retourn of spontaneous circulation (ROSC) at Bellvitge University Hospital (BUH) from 2009 to 2012. Develop a tracking sheet of the induced hypothermia process. Reflect professional experience of induced hypothermia after cardiac arrest through a case.</AbstractText>Retrospective descriptive study of the 54 cases, 45 men and 9 women, aged between ages 57 (15 to 80) years old treated with hypothermia after ROSC at BUH. Analysis of sociodemographic variables, specific variables and description of the inclusion criteria for hypothermia. Design of nursing record to express standardized care to undertake during the HI and its pilot trial. Monitoring a 60 years old patient who suffers cardiopulmonary arrest and is subjected to hypothermia.</AbstractText>Leading cause of cardiopulmonary arrest is acute coronary syndrome (ACS) (63%). Most representative initial rhythm is pulseless ventricular tachycardia/ventricular fibrillation (PVT/VF) (68.5%). There is longer survival in patients whose CPR is less than 30 minutes. The.target temperature of the patients was 33 °C for 24 hours, except for 5 patients who were stopped because of hemodynamic instability. At discharge, 54% were exitus, 4% had severe encephalopathy, 11% mild encephalopathy and 31% without neurological sequel. The applicability of the nursing record that was created for the HI process was checked, which allowed a fast overview of the procedure. It describes the clinical status of the case on admission, during the HI, at 48 hours, at discharge from the coronary care unit (CCU) and at discharge.</AbstractText>The data collected between 2009 and 2012 of patients with cardiopulmonary arrest candidates to hypothermia showed a favorable neurological recovery within the surviving patients. Additionally, patients with cardiopulmonary arrest not prolonged have a better prognosis agreeing with ROSC previous studies.</AbstractText>Hypothermia is a viable therapy for patients who have undergone cardiopulmonary arrest. It is important to make a specific assessment of each case as well as agree the track record of care applied to these patients to subsequently allow their assessment.</AbstractText> |
10,587 | Pericardial fat is associated with ventricular tachyarrhythmia and mortality in patients with systolic heart failure. | Pericardial fat (PF) has been hypothesized to exert local pathogenic effects on nearby cardiac structures above and beyond that of systemic adiposity which might be associated with the presence of arrhythmia or even worse outcomes. The aims of this study was to characterize the relationship between PF and the prognosis in patients with systolic heart failure (HF).</AbstractText>This is a retrospective cohort study of a cardiac magnetic resonance imaging (CMRI) database from 2004 to 2011. Fifty patients with systolic HF underwent CMRI examinations were included. We also enrolled twenty patients with HF as the control group. The cine imaging was analyzed to derive total PF volumes, left ventricular volumes and mass and left ventricular ejection fraction by using a previously validated technique. The outcomes, including ventricular tachycardia (VT), ventricular fibrillation (VF) and total mortality were obtained by reviewing medical records.</AbstractText>After a median follow-up of 694 days, patients with VT/VF had significant larger indexed PF volumes than those without [36.3 (32.8-43.1) ml/m(2) vs. 24.1 (20.2-27.6) ml/m(2), p = 0.001]. The mortality group also had significant larger indexed PF volumes (PF/body surface area) than those without [31.3 (22.8-38.4) ml/m(2) vs. 23.9 (19.8-27.3) ml/m(2), p = 0.010]. Indexed PF volumes were associated with the development of VT/VF (Hazard ratio, 7.510; 95% C.I, 0.901-62.582, p = 0.062) and mortality (Hazard ratio, 3.998; 95% C.I, 1.077-14.845, p = 0.038) by Cox's regression analyses.</AbstractText>PF is associated with the development of VT/VF and long-term overall mortality in patients with systolic HF.</AbstractText>Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
10,588 | Prognostic value of late gadolinium enhancement in dilated cardiomyopathy patients: a meta-analysis. | To evaluate the association between late gadolinium enhancement (LGE) at cardiac magnetic resonance (CMR) and major adverse events in dilated cardiomyopathy (DCM) patients.</AbstractText>Databases, including PubMed, Ovid, and EMBASE, were searched for studies evaluating LGE at CMR in DCM patient prognostication. Clinical outcomes were analysed using fixed-effects models or, in cases of significant heterogeneity, random-effects models.</AbstractText>In the meta-analysis of 13 studies on 1675 DCM patients with a mean follow-up of 3 years, LGE is associated with all-cause mortality (pooled odds ratio, 3.43 [95% confidence interval, 2.26-5.22], p<0.00001), cardiac death/transplantation (3.65 [1.80-7.40], p=0.0003), hospitalisation for heart failure (2.87 [1.53-5.39], p=0.001), major arrhythmia events (sudden cardiac death, sustained ventricular tachycardia or fibrillation, appropriate implantable cardioverter-defibrillator (ICD) discharge/pacing, and syncope: 4.24 [2.95-6.08], p<0.00001), and sudden cardiac death (3.33 [1.80-6.17], p=0.0001).</AbstractText>LGE in DCM patients appears to be associated with mortality and major cardiac events, underscoring its potential as an independent index for risk stratification and treatment guidance.</AbstractText>Copyright © 2015 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.</CopyrightInformation> |
10,589 | Coronary embolism causing acute inferior wall and ventricular myocardial infarction in a patient with rheumatic valvular heart disease: treatment with thrombus aspiration. | An elderly man with rheumatic valvular heart disease and atrial fibrillation presented with acute myocardial infarction. A coronary angiogram revealed complete occlusion of the right coronary artery (RCA), and we therefore considered that a thrombus might have obstructed the ostium of the RCA. We used a guiding catheter and the syringe of an aspiration device to remove two large dark red thrombi. A subsequent angiogram revealed that blood flow through the RCA had recovered, and the endomembrane of the RCA was smooth, with no evidence of stenosis or residual thrombus. In this case, thrombus aspiration via a guiding catheter was efficacious for treating this type of coronary embolism. |
10,590 | Varicella-zoster virus encephalomyelitis with a prominent demyelinating component. | The histopathologic presentation of varicella-zoster virus (VZV) infection of the central nervous system is varied and is not well understood. Here we report a case of VZV encephalomyelitis with prominent demyelinating pathology in a patient with a history of follicular lymphoma treated with allogeneic stem cell transplantation. The patient presented with waxing and waning bilateral limb weakness and mental status changes. MRI showed leptomeningeal, peripheral spinal cord and periventricular cerebral white matter lesions in the brain, and polymerase chain reaction on cerebrospinal fluid detected VZV DNA. The patient expired from developing atrial fibrillation that rapidly progressed to ventricular fibrillation 10 days after admission to our hospital. Autopsy revealed macrophage-rich areas of demyelination in the spinal cord and cerebrum with relative preservation of axons associated with inclusion bodies and positive immunostaining for VZV. This case represents a rare example of VZV encephalomyelitis presenting with a predominantly demyelinating, "multiple sclerosis-like" pathology. The clinical and histopathologic findings and relevant literature are presented and discussed. |
10,591 | Intra-operative defibrillation testing and clinical shock efficacy in patients with implantable cardioverter-defibrillators: the NORDIC ICD randomized clinical trial. | This trial was designed to test the hypothesis that shock efficacy during follow-up is not impaired in patients implanted without defibrillation (DF) testing during first implantable cardioverter-defibrillator (ICD) implantation.</AbstractText>Between February 2011 and July 2013, 1077 patients were randomly assigned (1 : 1) to first time ICD implantation with (n = 540) or without (n = 537) DF testing. The intra-operative DF testing was standardized across all participating centres, and all ICD shocks were programmed to 40 J irrespective of DF test results. The primary end point was the average first shock efficacy (FSE) for all true ventricular tachycardia and fibrillation (VT/VF) episodes during follow-up. The secondary end points included procedural data, serious adverse events, and mortality. During a median follow-up of 22.8 months, the model-based FSE was found to be non-inferior in patients with an ICD implanted without a DF test, with a difference in FSE of 3.0% in favour of the no DF test [confidence interval (CI) -3.0 to 9.0%, Pnon-inferiority <0.001 for the pre-defined non-inferiority margin of -10%). A total of 112 procedure-related serious adverse events occurred within 30 days in 94 patients (17.6%) tested compared with 89 events in 74 patients (13.9%) not tested (P = 0.095).</AbstractText>Defibrillation efficacy during follow-up is not inferior in patients with a 40 J ICD implanted without DF testing. Defibrillation testing during first time ICD implantation should no longer be recommended for routine left-sided ICD implantation.</AbstractText>© The Author 2015. Published by Oxford University Press on behalf of the European Society of Cardiology.</CopyrightInformation> |
10,592 | Temporal distribution of arrhythmic events in chronic kidney disease: Highest incidence in the long interdialytic period. | Chronic kidney disease (CKD) patients undergoing hemodialysis (HD) have a high risk of sudden cardiac death (SCD). A unique risk factor may be a longer interval between HD sessions (interdialytic period). Inherent in conventional HD (thrice-weekly) are two 48-hour short breaks (SIDP) and one 72-hour long break (LIDP) between HD sessions.</AbstractText>We used an implantable cardiac monitor (ICM) to define the incidence and timing of significant arrhythmias in an HD population.</AbstractText>Fifty CKD patients undergoing HD with left ventricular ejection fraction >35% had an ICM inserted, with intensive follow-up to record SCD events and predefined bradyarrhythmias and tachyarrhythmias.</AbstractText>Mean age of the patients was 67 ± 11 years; 72% were male, and the mean follow-up was 18 ± 4 months. There were 8 unexpected SCDs (16%), all during the LIDP. The terminal event was severe bradycardia with asystole in each recorded case. No episodes of polymorphic ventricular tachycardia (VT) occurred. A total of 7686 arrhythmia events were recorded in 43 patients (86%), including bradycardia in 15 patients (30%), sinus arrest in 14 (28%), second-degree atrioventricular block in 4 (8%), nonsustained VT in 10 (20%), and new-onset paroxysmal atrial fibrillation in 14 (28%). The LIDP was the highest-risk period for all arrhythmias (P < .001). The arrhythmia event rate per hour was greatest during the first pre-HD period of the week compared with any other peri-HD period (P < .001).</AbstractText>Risk of SCD and significant arrhythmias is greatest during the LIDP. SCD was attributable to severe bradycardia and asystole. Interventions to prevent this type of SCD or shorten the LIDP deserve further evaluation.</AbstractText>URL: https://www.anzctr.org.au (Unique identifier: ACTRN12613001326785).</AbstractText>Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
10,593 | Temporary biventricular pacing improves bypass graft flows in coronary artery bypass graft patients with permanent atrial fibrillation. | We have previously demonstrated the impact of univentricular pacing modalities on bypass graft flow (BGF) in the coronary artery bypass graft (CABG) patient with permanent atrial fibrillation (AF). The aim of the present study was to determine the mechanism of this improved coronary conduit and, in addition, to explore the possible benefits with biventricular pacing in patients with and without severe left ventricular dysfunction.</AbstractText>In 43 CABG patients [mean age 69.5 ± 1.3 years; ejection fraction (EF) 49 ± 2%] with AF, we analysed coronary vascular resistances (CVRs) and the contemporary changes in the BGF obtained during right ventricular outflow tract (RVOT), right- (RV), left- (LV) and right-left ventricular pacing (biventricular pacing, BiVP) using the ultrasonic transit-time methodology.</AbstractText>BiVP resulted in the highest percentage decrease of CVR in the overall study group by 17.5 ± 3.0% (P < 0.001), followed by RVOT pacing with 13.9 ± 3.9%. Accordingly, the highest mean BGF was achieved during BiVP, resulting in a 21.6 ± 2.6% increase when compared with no pacing and 16 ± 3.7% when compared with RV pacing. Analysis of patients according to their preoperative LV function (EF ≥50%, n = 26; EF <50%, n = 17) showed significantly lower CVR (P < 0.037) and higher BGF during BiVP in patients with lower EF.</AbstractText>Placement of an additional LV pacing wire offered a significant improvement in BGF by minimizing CVR in patients with AF and poor EF.</AbstractText>© The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.</CopyrightInformation> |
10,594 | Prevalence and predictors of early cardiovascular events after kidney transplantation: evaluation of pre-transplant cardiovascular work-up. | Cardiovascular disease is the leading cause of mortality after renal transplantation. The purpose of this study was to analyze cardiovascular risk factors at transplantation, occurrence of cardiovascular events in the first year after transplantation and evaluate pre-transplant work-up.</AbstractText>In total, 244 renal transplant recipients older than 50 years were included. The results of pre-transplant work-up, including clinical evaluation, electrocardiogram, echocardiography, myocardial perfusion testing and coronary angiography were analyzed.</AbstractText>Patients had multiple risk factors at inclusion on renal transplantation waiting list as high blood pressure (94.7%), dyslipidemia (81.1%), smoking (45.3%), diabetes (23.6%), past history of cardiovascular disease (21.3%) and obesity (12.7%). Following transplantation, 15.5% (n = 38) of patients experienced a cardiovascular event, including 2.8% (n = 7) acute coronary syndrome, 5.8% (n = 14) isolated increase in troponin level and 5.3% (n = 13) new onset atrial fibrillation. The pre-transplant parameters associated with a cardiovascular event were a past medical history of cardiovascular disease (HR = 2.06 [1.06-4.03], p = 0.03), echocardiographic left ventricular hypertrophy (HR = 2.04 [1.04-3.98], p = 0.037) and abnormal myocardial perfusion testing (HR = 2.25 [1.09 -5.96], p = 0.03). Pre-transplantation evaluation allowed the diagnosis of unknown coronary artery lesions in 8.9% of patients.</AbstractText> |
10,595 | Slow Heart Rate Predicts New Occurrence of Atrial Fibrillation. | This study aims to investigate the relation between baseline heart rate and new occurrence of AF in patients with mild symptoms.</AbstractText>Patients without pre-existing AF or structural heart disease who underwent 24-hour electrocardiogram (ECG) monitoring for palpitations, dizziness or syncope were followed up for new-onset AF.</AbstractText>428 patients (mean age 66.6±10.2 years, 43.7% male) were classified according to the average heart rate into four quartiles (1(st) quartile: <63 beat per minute (bpm); 2(nd) quartile: 63-70 bpm; 3(rd) quartile 70-77 bpm; and 4(th) quartile: >77 bpm). There were no significant differences in gender, prevalence of diabetes, hypertension, left ventricular ejection fraction, or medications but a higher prevalence of coronary artery disease was noted among patients in the lower quartiles of average heart rate. After a mean follow-up of 5.8±1.8 years, 60 patients (14.0%) developed new-onset AF. The annual incidence of new-onset AF was highest amongst those at the lowest quartile of average heart rate (9.39%/year) as compared to those amongst other quartiles. Cox regression analysis revealed that increasing age, decreasing quartile of average heart rate, and the use of calcium channel blocker were associated with increased risk of new-onset AF.</AbstractText>Average heart rate predicts new AF.</AbstractText>Copyright © 2015. Published by Elsevier B.V.</CopyrightInformation> |
10,596 | Effects of new class III antiarrhythmic drug niferidil on electrical activity in murine ventricular myocardium and their ionic mechanisms. | A new class III antiarrhythmic drug niferidil has been recently introduced as a highly effective therapy cure for cases of persistent atrial fibrillation, but ionic mechanisms of its action are still unknown. Effects of niferidil on action potential (AP) waveform and major ionic currents were studied in mouse ventricular myocardium. APs were recorded with glass microelectrodes in multicellular preparations of right ventricular wall. Whole-cell patch-clamp technique was used to measure K(+), Ca(2+), and Na(+) currents in isolated mouse ventricular myocytes. While 10(-7) M niferidil failed to alter the AP configuration, 10(-6) M tended to prolong APs (by 12.05 ± 1.8% at 50% of repolarization) and 10(-5) M induced significant slowing of repolarization (32.1 ± 4.9% at 50% of repolarization). Among the potassium currents responsible for AP repolarization phase, IK1 was found to be almost insensitive to niferidil. Ito demonstrated low sensitivity to niferidil with IC50 = 2.03 × 10(-4) M. IKur, which was previously hypothesized to be the main target of the drug, was more sensitive with IC50 = 6 × 10(-5) M. However, sustained delayed rectifier potassium current Iss was inhibited with even lower IC50 = 2.8 × 10(-5) M. Therefore, suppression of Iss and, second, IKur by niferidil seems to underlie the AP prolongation in mouse ventricular tissue. Niferidil also produced a modest decrease in ICaL peak amplitude (IC50≈10(-4) M), but failed to alter INa significantly. Niferidil prolongs APs in mouse ventricular myocardium mainly by inhibiting Iss and IKur K(+) currents, but not exclusively IKur, as was proposed earlier. Further investigations are required to reveal the mechanisms of niferidil action in human myocardium, where IKr is strongly expressed instead of Iss. |
10,597 | Late Gadolinium Enhancement on Cardiac MRI Correlates with QT Dynamicity Represented by QT/RR Relationship in Patients with Ventricular Arrhythmias. | The distribution of late gadolinium enhancement (LGE) on the cardiac MRI (CMR) indicates myocardial fibrosis and provides information of possible reentry substrates. QT dynamicity reflecting repolarization abnormalities has gained attention as a potential prognostic predictive factor.</AbstractText>To clarify the correlation between the LGE distribution on CMR and QT dynamicity represented by the QT/RR relationship.</AbstractText>CMR and QT/RR analyses using Holter monitoring were performed in 34 patients (24 males, 60 ± 11 years) with ventricular tachycardia (VT) and/or ventricular fibrillation (VF). The LGE on CMR was scored using a 4-point score in 17 left ventricular segments. The sum of the LGE scores was calculated for each patient. The QT/RR slope and daytime/nighttime QT/RR ratio (day/night ratio) were calculated. The correlation between the slope or the day/night QT/RR ratio and late enhancement findings was analyzed.</AbstractText>All patients were divided into 23 LGE positive (LGE(+)) and 11 LGE negative (LGE(-)) patients. The slopes of the QTe/RR and QTa /RR were significantly steeper in the LGE(+) than in LGE(-) patients (0.21 ± 0.03 vs 0.13 ± 0.02; P < 0.001, 0.19 ± 0.03 vs 0.13 ± 0.02; P < 0.001, respectively), and both slopes were significantly correlated with the total LGE scores (r = 0.83, P < 0.001; r = 0.71, P < 0.001, respectively). In the LGE(+) patients, the QTe day/night (1.37 ± 0.38 vs 0.91 ± 0.33; P = 0.002) and QTa day/night ratios (1.33 ± 0.26 vs 1.06 ± 0.30; P = 0.011) were significantly greater than those in the LGE(-) patients.</AbstractText>The LGE distribution was closely related to the QT dynamicity, suggesting that a combination of these markers can be a powerful tool for understanding the background pathophysiology.</AbstractText>© 2015 Wiley Periodicals, Inc.</CopyrightInformation> |
10,598 | Galectin-3 and post-myocardial infarction cardiac remodeling. | This review summarizes the current literature regarding the involvement and the putative role(s) of galectin-3 in post-myocardial infarction cardiac remodeling. Post-myocardial infarction remodeling is characterized by acute loss of myocardium, which leads to structural and biomechanical changes in order to preserve cardiac function. A hallmark herein is fibrosis formation, both in the early and late phase following acute myocardial infarction. Galectin-3, a β-galactoside-binding lectin, which is a shared factor in fibrosis formation in multiple organs, has an established role in cardiac fibrosis in the setting of pressure overload, neuro-endocrine activation and hypertension, but its role in post- myocardial infarction remodeling has received less attention. However, accumulative experimental studies have shown that myocardial galectin-3 expression is upregulated after myocardial infarction, both on mRNA and protein level. This already occurs shortly after myocardial infarction in the infarcted and border zone area, and also at a later stage in the spared myocardium, contributing to tissue repair and fibrosis. This is associated with typical aspects of fibrosis formation, such as apposition of matricellular proteins and increased factors of collagen turnover. Interestingly, myocardial fibrosis in experimental post-myocardial infarction cardiac remodeling could be attenuated by galectin-3 inhibition. In clinical studies, circulating galectin-3 levels have been shown to identify patients at risk for new-onset heart failure and atrial fibrillation. Circulating galectin-3 levels also predict progressive left ventricular dilatation after myocardial infarction. From literature we conclude that galectin-3 is an active player in cardiac remodeling after myocardial infarction. Future studies should focus on the dynamics of galectin-3 activation after myocardial infarction, and study the possibilities to target galectin-3. |
10,599 | Left atrial mechanical function and stiffness in patients with atrial septal aneurysm: a speckle tracking study. | Atrial septal aneurysm (ASA) is a risk factor for arterial embolism. Atrial dysfunction and atrial arrhythmia, such as atrial fibrillation, might represent a mechanism for arterial embolism in such patients. Speckle tracking echocardiography (STE) is a novel and promising tool for detecting early changes in left atrial (LA) myocardial dysfunction. The aim of the study was to evaluate LA mechanical function and stiffness in ASA patients by 2-dimensional STE strain parameters.</AbstractText>Thirty-four ASA patients (44.2 ± 12.3 years, 15 male) were studied, using a STE, and were compared with 31 age, gender, and left ventricular (LV) mass-matched controls (41.8 ± ± 11.5 years, 14 male). LA volume indices, mitral annular velocities, and global longitudinal LA strain were measured. The ratio of E/e' to LA strain was used as an index of LA stiffness.</AbstractText>Patients with ASA showed increased LA volume indices and decreased LA global strain (25.3 ± 5.2 vs. 42.1 ± 8.7, p < 0.001). LA stiffness was increased in patients with ASA compared to the control subjects (0.41 ± 0.15 vs. 0.14 ± 0.05, p < 0.001), and LA strain and stiffness were related with LA volume indices.</AbstractText>Patients with ASA have decreased LA global strain and increased stiffness, in comparison with those of the control subjects. LA strain and stiffness were significantly related with LA volume indices. LA stiffness and strain can be used for the assessment of LA function in patients with ASA.</AbstractText> |
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