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11,500 | Clinical impact of defibrillation testing at the time of implantable cardioverter-defibrillator insertion. | Ventricular fibrillation is routinely induced during implantable cardioverter-defibrillator insertion to assess defibrillator performance, but this strategy is experiencing a progressive decline. We aimed to assess the efficacy of defibrillator therapies and long-term outcome in a cohort of patients that underwent defibrillator implantation with and without defibrillation testing.</AbstractText>Retrospective observational series of consecutive patients undergoing initial defibrillator insertion or generator replacement. We registered spontaneous ventricular arrhythmias incidence and therapy efficacy, and mortality.</AbstractText>A total of 545 patients underwent defibrillator implantation (111 with and 434 without defibrillation testing). After 19 (range 9-31) months of follow-up, the death rate per observation year (4% vs. 4%; p = 0.91) and the rate of patients with defibrillator-treated ventricular arrhythmic events per observation year (with test: 10% vs. without test: 12%; p = 0.46) were similar. The generalized estimating equations-adjusted first shock probability of success in patients with test (95%; CI 88-100%) vs. without test (98%; CI 96-100%; p = 0.42) and the proportion of successful antitachycardia therapies (with test: 87% vs. without test: 80%; p = 0.35) were similar between groups. There was no difference in the annualized rate of failed first shock per patient and per shocked patient between groups (5% vs. 4%; p = 0.94).</AbstractText>In this observational study, that included an unselected population of patients with a defibrillator, no difference was found in overall mortality, first shock efficacy and rate of failed shocks regardless of whether defibrillation testing was performed or not.</AbstractText> |
11,501 | Feasibility and effect of para-right bundle branch pacing in patients with atrial fibrillation and complete atrioventricular block. | Chronic right ventricular apex (RVA) pacing can induce negative clinical effects. The aim of the present study was to compare RVA pacing with para-right bundle branch (para-RBB) pacing in terms of electrocardiogram (ECG) and echocardiographic (ECHO) features.</AbstractText>Forty-one consecutive persistent atrial fibrillation patients with an indication for permanent pacing treatment due to complete atrioventricular block were randomly assigned to receive a screw-in lead either in the RVA (n = 22) or at the para-RBB (n = 19). Para-RBB pacing leads were located according to the RBB potential recorded by electrophysiology catheter. ECG was recorded before and after implantation. All patients underwent the pacemaker programming at 1 day, 6 months, 12 months and 24 months after implantation. ECHO examination was performed during follow-up at 6, 12 and 24 months after implantation to assess the heart function and synchronism.</AbstractText>There was no significant difference in pacing lead parameters between para-RBB pacing group and RVA pacing group. Compared with RVA pacing group, the para-RBB pacing group obtained a narrower QRS complex, more synchronic ventricular systole, and less negative effect on heart function (p < 0.05).</AbstractText>Para-RBB pacing has potential clinical benefits and may be a physiological pacing site.</AbstractText> |
11,502 | Left ventricular noncompaction - a case report. | Left Ventricular (LV) noncompaction is a rare disorder of endomyocardial morphogenesis. It has got a high mortality rate. It is frequently missed during diagnosis because of lack of suspicion and lack of definite diagnostic criteria. We are reporting a case of LV noncompaction in a Bangladeshi patient. Patient presented to us with history of repeated syncope. She had family history of sudden cardiac death. Clinically, there had a systolic murmur in left parasternal area. Her ECG showed different arrhythmia like atrial fibrillation, sinus bradycardia and Ventricular tachycardia. Her echocardiography showed features consistent with 'left ventricular noncompaction'. This is the first case report of this type in a Bangladeshi patient. |
11,503 | [Matrix metalloproteinases and hypertrophic cardiomyopathy]. | Prognosis of patients with hypertrophic cardiomyopathy (HCMP) to a great extent is determined by clinical variant of the disease. As the system of matrix metalloproteinases (MMPs) plays an important role in development and progression of the processes of fibroformation and tissue remodeling polymorphisms of modifier genes regulating its components can influence clinical course of HCMP. Among possible markers of prognostication of the course of cardiovascular diseases the role of MMPs and their tissue inhibitors has been discussed. With the aim of studying effects of MMPs on the course of HCMP we conducted this investigation in which we included 58 patients and a group of healthy volunteers (control group) with comparable sex and age. In all participants (n=112) we determined polymorphism of MMP-3 - rs3025058 and markers of fibroformation (MMP-3, TIMP-1, TIMP-2, and collagen IV). We found that unfavorable allele variant MMP-3 1171 was associated with hypertrophy of interventricular septum. We also established that levels of TIMP-1 in the group of patients with HCMP were significantly lowered in comparison with those in control group. Concentration of marker MMP-3 was elevated in the group of patients with variant "atrial fibrillation" compared with groups of stable course and progressing course. We revealed medium degree reverse correlation between MMP-3 marker and thickness of left ventricular posterior wall and direct correlation of this parameter with coefficient of asymmetry. Polymorphism MMP-3 - 1171 produced an impact on the level of TIMP-1 marker. The data obtained by us confirm effect of the system of MMPs on formation of hypertrophic remodeling of the heart in HCMP. |
11,504 | [Idiopathic arrhythmias: possibilities of complex nosological diagnosis, and differentiated treatment]. | of the study was to elucidate nosological nature of "idiopathic" arrhythmias by means of complex clinical-morphological examination and to assess efficacy of differentiated (including etiotropic and pathogenetic) treatment.</AbstractText>We examined 190 patients (117 women, mean age 45.33 ± 14.84 years) with "idiopathic" arrhythmias: atrial fibrillation (38.9%) (AF,) and flutter (11.1%), supraventricular (44.7%) and ventricular (55.3%) extrasystoles (SVE and VE), bouts of ventricular tachycardia (15.8%), atrioventricular block (22,6%) et al. Mean number of antiarrhythmic drugs per patient was 3 (from 1 to 8). Examination included Holter ECG monitoring, echocardiography, determination of anticardiac antibodies (97.4%) and markers of cardiotropic viruses (87.4%), treadmill test (26.3%), transesophageal cardiac pacing (12.1%), electrophysiological investigation (10%), multispiral computed tomography (22.1%), magnetic resonance tomography (21.6%), scintigraphy (27.4%), coronary angiography (10.0%), endomyocardial biopsy (EMB) (10.0%), DNA diagnostics (8.9%).</AbstractText>EMB revealed immune-inflammatory (myo/endocarditis, systemic/myocardial vasculitis) or genetic pathology in 78.9 and 21.1% of cases, respectively. Level of anticardiac antibodies (including specific antinuclear factor) most closely correlated with EMB findings. On the basis of comparison of EMB data with data of complex examination we created algorithm of nosological diagnostics in "idiopathic" arrhythmias. According to nosology all patients were distributed in the following way: 1) chronic infectious-immune myocarditis (n=144, 75.7%), morphologically verified in 14, viral in 27 patients; 2) genetic cardiomyopathy (n=15, 7.9%), morphologically verified in 4, virus positive in 1 (arrhythmogenic right ventricular dysplasia, non-compaction myocardium, Fabri disease, Brugada syndrome, undetermined); in 4 patients mutations in plakophilin 2, desmoglein, desmin, -galactosidase A genes were found; 3) combination of genetic diseases with myocarditis (n=18; 9.5%) including viral (n=3); 4) isolated myocardiodystrophy (tonsillogenic< dyshormonal, n=3, 1.6%); 5) proper idiopathic arrhythmias (n=10, 5.3%). Therapy of myocarditis included antiviral (43.2%) and immunosuppressive (76.3%) drugs. Cardiotropic and antiarrhythmic therapy was also administered. Only in patients with myocarditis it was possible to withdraw effective antiarrhythmic (16.7%) and to improve effect of previously ineffective drugs. Surgical treatment (implantation of pacemaker or cardioverter-defibrillator, radiofrequency ablation) was more frequently used in patients with genetic (39.4%) and idiopathic arrhythmias (53.8%) than in patients with myocarditis (16.0%).</AbstractText>Etiology of idiopathic arrhythmias can be established in most cases. Their main causes are immune-inflammatory diseases, genetic cardiomyopathies and their combination. Therapy of myocarditis improves antiarrhythmic activity of treatment, in some patients allows to withdraw antiarrhythmic drugs, decrease requirements in surgical treatment and to optimally prepare patients to radiofrequency ablation.</AbstractText> |
11,505 | The heart and brain imaging in lone atrial fibrillation - are we surprised? | "Lone" atrial fibrillation (AF) is generally used to refer to patients with AF in the absence of structural heart disease. When the decision for oral anticoagulation is discussed, "lone" AF refers to patients who do not have established stroke risk factors. Imaging is often used to rule out structural heart disease, e.g. coronary artery disease, peripheral vascular disease, mitral stenosis or left ventricular (LV) dysfunction. Imaging of the heart has a central role in establishing the "lone" aspect in patients with "lone"AF, similar to the measurement of blood glucose and blood pressure: Patients with structural heart disease, defined as e.g. reduced LV ejection fraction, clinical evidence for heart failure, or evidence for coronary artery disease, will not be considered as patients with "lone" AF. The search for these conditions requires some cardiac imaging, often done by echocardiography and non-invasive tests for coronary artery disease or ischemia. Increasingly, brain imaging is used to define the clinical diagnosis of a stroke, thus also contributing to the detection of stroke risk factors. Cerebral imaging in AF patients without competing causes for silent strokes or microbleeds ("lone" AF, rather used in the context of anticoagulation, i.e. clinical absence of structural heart disease) would allow to better understand the contribution of AF to these brain lesions. The assumption that silent strokes are likely drivers of cognitive dysfunction, and the fact that microbleeds put patients at risk for intracerebral hemorrhage, illustrates the need to collect information on brain imaging. In this review article, we summarize current data on heart and brain imaging in patients with "lone" AF and discuss their clinical implications for risk assessment and management of patients with "lone" AF. |
11,506 | Kinetics of left ventricular rotation during exercise and its relation to exercise tolerance in atrial fibrillation: assessment by two-dimensional speckle tracking echocardiography. | Left ventricular (LV) rotation plays an important role in cardiac function both at rest and during exercise in sinus rhythm. The kinetics of rotation during exercise and the relation between exercise tolerance and rotation-related parameters in patients with atrial fibrillation (AF) are unknown.</AbstractText>Twenty-nine patients (age 62 ± 13 years, 6 females) with AF and preserved LV ejection fraction (LVEF) were studied using two-dimensional speckle tracking echocardiography at rest and during exercise with a supine bicycle ergometer (20 W, 10 min). We measured the systolic rotation (Rot) and the peak rotation rate in systole and early diastole (eRotR) at the apical and basal levels of the LV. All patients underwent cardiopulmonary exercise testing to obtain their percent achieved of the predicted peak oxygen consumption (% peak VO2) value.</AbstractText>During exercise, apical Rot-related indices were significantly increased only in the preserved % peak VO2 group. In contrast, E/e' was significantly elevated only in the reduced % peak VO2 group. Multivariable stepwise regression analysis showed that apical ΔRot was independently associated with % peak VO2 (β = 0.72; p < 0.01). Apical ΔeRotR, which could not be selected as an independent predictor of % peak VO2, had a good linear correlation with apical ΔRot (r = 0.81, p < 0.01).</AbstractText>The augmentation of apical rotation in response to exercise may coincide with an increase of the apical derotation rate, and apical rotation reserve may reflect exercise tolerance in patients with AF and preserved LVEF.</AbstractText> |
11,507 | Moderate Hypothermia (33 °C) Decreases the Susceptibility to Pacing-Induced Ventricular Fibrillation Compared with Severe Hypothermia (30 °C) by Attenuating Spatially Discordant Alternans in Isolated Rabbit Hearts. | Severe hypothermia (SH, 30 °C) increases the risk of pacing-induced ventricular fibrillation (PIVF) by enhancing spatially discordant alternans (SDA). Whether moderate hypothermia (MH, 33 °C), which is clinically used for therapeutic hypothermia, also facilitates SDA remains unclear. We hypothesized that MH attenuates SDA occurrence compared with that achieved by SH, and decreases the susceptibility of PIVF.</AbstractText>Using an optical mapping system, action potential duration (APD)/conduction velocity restitutions and thresholds of APD alternans were determined by S1 pacing in Langendorff-perfused isolated rabbit hearts. In the MH group (n = 7), S1 pacing was performed at baseline (37 °C), after 5-min MH, and after 5-min rewarming (37 °C). In the SH group (n = 9), pacing was also performed at baseline (37 °C), after 5-min SH, and after 5-min rewarming (37 °C). The thresholds of APD alternans were defined as the longest S1 pacing cycle length at which APD alternans were detected.</AbstractText>Although the thresholds of APD alternans were not different between the MH (273 ± 46 ms) and the SH (300 ± 35 ms) (p = 0.281) groups, SDA threshold was shorter (at a faster heart rate) during MH (228 ± 33 ms) than that during SH (289 ± 42 ms) (p = 0.028). At APD alternans threshold, SH hearts showed more SDA than that during MH (SH: 7 hearts, MH: 2 hearts, p = 0.049). SDA could be induced in all 9 SH hearts (100%), while only 4 MH hearts (57%) had SDA (p = 0.029). The PIVF inducibility during SH (44 ± 53%) was higher than that during MH (0%) (p = 0.043).</AbstractText>Compared with SH, the MH group showed greater attenuation of SDA and decreased the susceptibility of PIVF. Therefore, MH is safer as a procedural guideline for use in clinical therapeutic hypothermia than SH.</AbstractText>Cardiac alternans; Conduction velocity; Hypothermia; Optical mapping.</AbstractText> |
11,508 | Novel α-actinin 2 variant associated with familial hypertrophic cardiomyopathy and juvenile atrial arrhythmias: a massively parallel sequencing study. | Next-generation sequencing might be particularly advantageous in genetically heterogeneous conditions, such as hypertrophic cardiomyopathy (HCM), in which a considerable proportion of patients remain undiagnosed after Sanger. In this study, we present an Italian family with atypical HCM in which a novel disease-causing variant in α-actinin 2 (ACTN2) was identified by next-generation sequencing.</AbstractText>A large family spanning 4 generations was examined, exhibiting an autosomal dominant cardiomyopathic trait comprising a variable spectrum of (1) midapical HCM with restrictive evolution with marked biatrial dilatation, (2) early-onset atrial fibrillation and atrioventricular block, and (3) left ventricular noncompaction. In the proband, 48 disease genes for HCM, selected on the basis of published reports, were analyzed by targeted resequencing with a customized enrichment system. After bioinformatics analysis, 4 likely pathogenic variants were identified: TTN c.21977G>A (p.Arg7326Gln); TTN c.8749A>C (p.Thr2917Pro); ACTN2 c.683T>C (p.Met228Thr); and OBSCN c.13475T>G (p.Leu4492Arg). The novel variant ACTN2 c.683T>C (p.Met228Thr), located in the actin-binding domain, proved to be the only mutation fully cosegregating with the cardiomyopathic trait in 18 additional family members (of whom 11 clinically affected). ACTN2 c.683T>C (p.Met228Thr) was absent in 570 alleles of healthy controls and in 1000 Genomes Project and was labeled as Damaging by in silico analysis using polymorphism phenotyping v2, as Deleterious by sorts intolerant from tolerant, and as Disease-Causing by Mutation Taster.</AbstractText>A targeted next-generation sequencing approach allowed the identification of a novel ACTN2 variant associated with midapical HCM and juvenile onset of atrial fibrillation, emphasizing the potential of such approach in HCM diagnostic screening.</AbstractText>© 2014 American Heart Association, Inc.</CopyrightInformation> |
11,509 | Early repolarisation and J wave syndromes. | J wave syndrome has emerged as a significant cause of Idiopathic ventricular fibrillation (IVF) responsible for sudden cardiac death. A large body of data is now available on genesis, genetics and ionic mechanisms of J wave syndromes. Two of these viz., Early repolarization syndrome (ER) and Brugada syndrome (BrS) are fairly well characterized enabling correct diagnosis in most patients. The first part of repolarization of ventricular myocardium is governed by Ito current i.e., rapid outward potassium current. The proposed mechanism of ventricular fibrillation (VF) and ventricular tachycardia (VT) storms is the faster Ito current in the epicardium than in the endocardium results in electrical gradient that forms the substrate for phase 2 reentry. Prevention of Ito current with quinidine supports this mechanism. Majority of ER patterns in young patients are benign. The key issue is to identify those at increased risk of sudden cardiac death. Association of both ER syndrome and Brugada syndrome with other disease states like coronary artery disease has also been reported. Individuals resuscitated from VF definitely need an implantable cardiac defibrillator (ICD) but in others there is no consensus regarding therapy. Role of electrophysiology study to provoke ventricular tachycardia or fibrillation is not yet well defined. Radiofrequency ablation of epicardial substrate in right ventricle in Brugada syndrome is also under critical evaluation. In this review we shall discuss historical features, epidemiology, electrocardiographic features, ionic pathogenesis, clinical features and current status of proposed treatment of ER and BrS. |
11,510 | Left ventricular dysfunction after mitral valve repair--the fallacy of "normal" preoperative myocardial function. | A proportion of patients experience a decrease in left ventricular (LV) ejection fraction (EF) after mitral valve repair; however, predictors and long-term consequences remain unclear.</AbstractText>A study of 1705 patients with severe, degenerative mitral valve regurgitation and normal preoperative EF (>60%) undergoing mitral valve repair from 1993 to 2012 was performed. Multivariate logistic regression and Cox proportional hazards models were used to determine the predictors of early postoperative LV dysfunction (EF < 50%) and long-term survival, respectively.</AbstractText>Postoperative outcomes were comparable between patients; however, those with an EF of <50% (n = 314, 18.4%) had significantly greater enlargement in systolic dimension (left ventricular end-systolic diameter, -0.6 vs 4.3 mm; P < .001) and decrease in right ventricular systolic pressure (-2.7 vs -7.8 mm Hg; P < .001) immediately after repair. On longitudinal follow-up, early LV impairment persisted, with EF recovering to preoperative levels (>60%) in only one third of patients with postrepair EF <50% versus two thirds of those with an EF of ≥ 50% (P < .001). The overall survival at 5, 10, and 15 years of follow-up was 95%, 85%, and 70.8%, respectively. Although early postoperative EF < 50% was not a significant determinant of late survival, when adjusting for older age (hazard ratio [HR], 1.09), hypertension (HR, 1.38), New York Heart Association class III or IV (HR, 1.71), and preoperative atrial fibrillation (HR, 2.33), postoperative EF < 40% conferred a 70% increase in the hazard of late death (HR, 1.74; 95% confidence interval, 1.03-2.92; P = .037). A preoperative right ventricular systolic pressure >49 mm Hg and left ventricular end-systolic diameter >36 mm were independently associated with a 4.4- and 6.5-fold increased risk of developing a postoperative EF < 40% (P < .001, for both).</AbstractText>De novo postoperative LV dysfunction is not uncommon in patients with "normal" preoperative EF undergoing mitral valve repair. LV dysfunction can persist, impairing recovery of LV size, function, and survival. The consideration of mitral repair before the onset of excessive LV dilation or pulmonary hypertension, even in those with preserved EF, seems warranted.</AbstractText>Copyright © 2014 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,511 | Rapidly switching multidirectional defibrillation: reversal of ventricular fibrillation with lower energy shocks. | Cardiac arrest after open surgery has an incidence of approximately 3%, of which more than 50% of the cases are due to ventricular fibrillation. Electrical defibrillation is the most effective therapy for terminating cardiac arrhythmias associated with unstable hemodynamics. The excitation threshold of myocardial microstructures is lower when external electrical fields are applied in the longitudinal direction with respect to the major axis of cells. However, in the heart, cell bundles are disposed in several directions. Improved myocardial excitation and defibrillation have been achieved by applying shocks in multiple directions via intracardiac leads, but the results are controversial when the electrodes are not located within the cardiac chambers. This study was designed to test whether rapidly switching shock delivery in 3 directions could increase the efficiency of direct defibrillation.</AbstractText>A multidirectional defibrillator and paddles bearing 3 electrodes each were developed and used in vivo for the reversal of electrically induced ventricular fibrillation in an anesthetized open-chest swine model. Direct defibrillation was performed by unidirectional and multidirectional shocks applied in an alternating fashion. Survival analysis was used to estimate the relationship between the probability of defibrillation and the shock energy.</AbstractText>Compared with shock delivery in a single direction in the same animal population, the shock energy required for multidirectional defibrillation was 20% to 30% lower (P < .05) within a wide range of success probabilities.</AbstractText>Rapidly switching multidirectional shock delivery required lower shock energy for ventricular fibrillation termination and may be a safer alternative for restoring cardiac sinus rhythm.</AbstractText>Copyright © 2014 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,512 | ICD Therapy In RVOT-VT And Early Stage ARVD/C Patients. | Implantable cardioverter-defibrillators (ICDs) improve the survival of patients with ischemic or non-ischemic cardiomyopathy and a reduced ejection fraction. However, the efficacy of ICD therapy in patients with right ventricular outflow tract ventricular tachycardia (RVOT-VT) and early stage arrhythmogenic right ventricular dysplasia / cardiomyopathy (ARVD/C) has not been well clarified. Although the prognosis of RVOT-VT is generally good, malignant forms of RVOT-VT resulting in polymorphic VT have been reported by several investigators. Radiofrequency catheter ablation is still effective in such patients, and thus an ICD implantation is usually not required. On the other hand, according to the current guidelines in patients with ARVD/C, an ICD implantation is recommended for secondary prevention when the patients develop sustained VT or VF. An ICD implantation may also be considered for primary prevention in high-risk patients: extensive disease, family history of sudden cardiac death, or undiagnosed syncope. Since an ICD implantation in the early stage of ARVD/C is controversial, physicians should well consider its risks and benefits. Early intervention with ICD therapy in ARVD/C patients may reduce the arrhythmic death rate but increases the device related complications especially in younger patients. |
11,513 | Verapamil reduces incidence of reentry during ventricular fibrillation in pigs. | The characteristics of reentrant circuits during short duration ventricular fibrillation (SDVF; 20 s in duration) and the role of Ca(++) and rapid-activating delayed rectifier potassium currents during long duration ventricular fibrillation (LDVF; up to 10 min in duration) were investigated using verapamil and sotalol. Activation mapping of the LV epicardium with a 21 × 24 electrode plaque was performed in 12 open-chest pigs. Pigs were given either verapamil (0.136 mg/kg) or sotalol (1.5 mg/kg) and verapamil. Reentry patterns were quantified for SDVF, and, for LDVF, activation patterns were compared with our previously reported control LDVF data. Verapamil significantly increased conduction velocity around the reentrant core by 10% and reduced the reentrant cycle length by 15%, with a net reduction in reentry incidence of 70%. Sotolol had an opposite effect of decreasing the conduction velocity around the core by 6% but increasing the reentrant cycle length by 13%, with a net reduction of reentry incidence of 50%. After 200 s of VF, verapamil significantly slowed wavefront conduction velocity and activation rate compared with control data. Verapamil decreased the incidence of reentry in SDVF by accelerating conduction velocity to increase the likelihood of conduction block, possibly through increased sympathetic tone. The drug slowed activation rate and conduction velocity after 200 s of VF, suggesting that L-type Ca(++) channels remain active and may be important in the maintenance of LDVF. Sotalol in addition to verapamil caused no additional antiarrhythmic effect. |
11,514 | Analyzing cardiac rhythm in the presence of chest compression artifact for automated shock advisory. | Defibrillation is often required to terminate a ventricular fibrillation or fast ventricular tachycardia rhythm and resume a perfusing rhythm in sudden cardiac arrest patients. Automated external defibrillators rely on automatic ECG analysis algorithms to detect the presence of shockable rhythms before advising the rescuer to deliver a shock. For a reliable rhythm analysis, chest compression must be interrupted to prevent corruption of the ECG waveform due to the artifact induced by the mechanical activity of compressions. However, these hands-off intervals adversely affect the success of treatment. To minimize the hands-off intervals and increase the chance of successful resuscitation, we developed a method which asks for interrupting the compressions only if the underlying ECG rhythm cannot be accurately determined during chest compressions. Using this method only a small percentage of cases need compressions interruption, hence a significant reduction in hands-off time is achieved. Our algorithm comprises a novel filtering technique for the ECG and thoracic impedance waveforms, and an innovative method to combine analysis from both filtered and unfiltered data. Requiring compression interruption for only 14% of cases, our algorithm achieved a sensitivity of 92% and specificity of 99%. |
11,515 | Left atrial deformation predicts success of first and second percutaneous atrial fibrillation ablation. | Predictors of second radiofrequency catheter ablation (RFCA) success are not well known. Surgical ablation is accepted for failed first RFCA, but second RFCA has fewer complications.</AbstractText>The purpose of this study was to evaluate left atrial (LA) size and function as potential predictors of second RFCA for atrial fibrillation (AF).</AbstractText>Thirty-three healthy volunteers (group I) and 83 patients with symptomatic drug-refractory AF treated with a first RFCA (group II, n = 48) or a second RFCA (group III, n = 35 patients) were included. Echocardiography was performed in all patients in sinus rhythm before RFCA and in all volunteers. LA size and function were measured using longitudinal strain and strain rate during ventricular systole (LASs, LASRs) and during early diastole (LASRe) or late diastole (LASRa) with speckle tracking echocardiography. The effectiveness of RFCA on arrhythmia recurrence was evaluated at 6-month follow-up.</AbstractText>LASs, LASRs, and LASRa were significantly lower in group III patients compared to other groups (P < .001 for all). LA diameter or volumes did not predict success after RFCA. LASs was an independent predictor of arrhythmia suppression after a first RFCA and after a second RFCA, with the best cutoff at LASs >20% (sensitivity 86%, specificity 70%) and LASs >12% (sensitivity 84%, specificity 90%), respectively.</AbstractText>LA myocardial deformation imaging is a reliable tool for predicting success after a first and a second RFCA. These parameters could improve candidate selection, especially for a second RFCA.</AbstractText>Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,516 | Malignant multivessel coronary spasm complicated by myocardial infarction, transient complete heart block, ventricular fibrillation, cardiogenic shock and ischemic stroke. | Multivessel coronary spasm resulting to cardiogenic shock and malignant ventricular arrhythmias though rare has been reported in the literature. The disease seems to be more prevalent in Asians. There have been isolated reports of coronary spasm in patients with reactive airway disease. We report the first case of spontaneous multivessel spasm in a male patient with bronchial asthma of Arab ethnicity resulting in acute myocardial infarction complicated by cardiogenic shock, recurrent ventricular arrhythmias, and transient complete heart block. Literature review of similar cases suggests a strong association with bronchial asthma and a more malignant course in patients with reactive airway disease. The role of intracoronary nitroglycerin in proving the diagnosis even in patients in shock on maximal inotropic supports and intra-aortic balloon pump is highlighted and the importance of considering multivessel coronary spasm as a cause for acute coronary syndrome even in patients with conventional risk factors for atherosclerotic coronary artery disease is reinforced in the discussion of this case. |
11,517 | Follow-up of implantable cardioverter-defibrillator therapy: comparison of coronary artery disease and dilated cardiomyopathy. | Since several large trials have proven the effectiveness of implantable cardioverter-defibrillators (ICDs) in patients with left ventricular dysfunction, disadvantages have become more apparent. As the prognosis of patients with cardiovascular diseases is improving, assessment of ICD patients and re-evaluation of the current guidelines is mandatory. We aimed to evaluate differences in mortality and occurrence of (in)appropriate shocks in ICD patients with coronary artery disease (CAD) or dilated cardiomyopathy (DCM).</AbstractText>In a large teaching hospital, all consecutive patients with systolic dysfunction due to CAD or DCM who received an ICD with and without resynchronisation therapy, were collected in a database.</AbstractText>A total of 320 consecutive patients (age 67 ± 10 years) were classified as CAD patients and 178 (63 ± 11 years) as DCM patients. Median follow-up was 40 months (interquartile range [IQR] 23─57 months). All-cause mortality was 14 % (CAD 15 % vs DCM 13 %). Appropriate shocks occurred in 13 % of all patients (CAD 15 % vs DCM 11 %, p = 0.12) and inappropriate shocks occurred in 10 % (CAD 8 % vs DCM 12 %, p = 0.27). Multivariate analysis demonstrated impaired left ventricular ejection fraction, QRS >120, age ≥75 years and low estimated glomerular filtration rate as predictors for all-cause mortality. Predictors for inappropriate shocks were permanent and paroxysmal atrial fibrillation.</AbstractText>Mortality rates were similar in patients with CAD and DCM who received an ICD. Furthermore, no differences were found in the occurrence of appropriate and inappropriate ICD interventions between these patient groups.</AbstractText> |
11,518 | Development of a closed-artery catheter-based myocardial infarction in pigs using sponge and lidocaine hydrochloride infusion to prevent irreversible ventricular fibrillation. | The objectives of this study were to develop a robust, homogeneous, viable and inexpensive model of closed-artery catheter-based model of myocardial infarction (MI) in pigs without major cardiac dysfunction. Suitable animal models that mimic human cardiovascular conditions are of paramount importance to understand the effects of novel therapeutic strategies to improve tissue perfusion and prevent cardiac deterioration post-MI. Pigs (N = 21, BW = 17 ± 1 kg) receiving continuous iv lidocaine hydrochloride were subjected to percutaneous intracoronary implant of foam sponge into the proximal left circumflex coronary artery. Intraprocedure mortality was 23.8%. ST segment elevation and increased serum Troponin T and CK-MB were documented in all animals. Thirty days after occlusion, echocardiography (95% IC [9.3-12.4%]) and anatomopathological (95% CI [9.3-12.6%]) analyses confirmed a significant and reproducible MI. Taken together, we provide evidence for a suitable closed-artery catheter-based method to produce MI in pigs accompanied by tissue hypoperfusion and absence of overt heart failure. |
11,519 | [The development of ventricular fibrillation due to etomidate for anesthetic induction: a very rare side effect, case report]. | Ventricular fibrillation occurring in a patient can result in unexpected complications. Here, our aim is to present a case of ventricular fibrillation occurring immediately after anesthesia induction with etomidate administration.</AbstractText>A fifty-six-year-old female patient with a pre-diagnosis of gallstones was admitted to the operating room for laparoscopic cholecystectomy. The induction was performed by etomidate with a bolus dose of 0.3mg/kg. Severe and fast adduction appeared in the patient's arms immediately after induction. A tachycardia with wide QRS and ventricular rate 188beat/min was detected on the monitor. The rhythm turned to VF during the preparation of cardioversion. Immediately we performed defibrillation to the patient. Sinus rhythm was obtained. It was decided to postpone the operation due to the patient's unstable condition.</AbstractText>In addition to other known side effects of etomidate, very rarely, ventricular tachycardia and fibrillation can be also seen. To the best of our knowledge, this is the first case regarding etomidate causing VF in the literature.</AbstractText>Copyright © 2013 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.</CopyrightInformation> |
11,520 | Complete His-ventricular block, atrial flutter and ventricular tachycardia as arrhythmogenic activities in a patient with takotsubo cardiomyopathy. | An association of atrial arrhythmias with takotsubo cardiomyopathy (TTC) has not been described previously. Here we report a 65-year-old male patient with TTC. The sudden appearance of atrioventricular block and subsequent bradycardia are believed to be key contributing factors for the development of TTC. Both ventricular tachyarrhythmia and various atrial arrhythmias, such as atrial flutter and atrial fibrillation, were observed during the initial management of the patient's TTC. We speculate that both the left ventricular contractile dysfunction and the arrhythmogenic activities may share a common underlying etiology in advanced heart failure patients with TTC. <<b>Learning objective:</b> We describe a case of TTC complicated by ventricular tachycardia, atrial tachyarrhythmias, and an atrioventricular conduction disturbance and discuss the etiology of arrhythmogenic activities in TTC.>. |
11,521 | Interposed abdominal compression-cardiopulmonary resuscitation after cardiac surgery. | The management of cardiac arrest after cardiac surgery differs from the management of cardiac arrest under other circumstances. In other studies, interposed abdominal compression-cardiopulmonary resuscitation (IAC-CPR) resulted in a better outcome compared with conventional CPR. The aim of the present study was to determine the feasibility, safety and efficacy of IAC-CPR compared with conventional CPR in patients with cardiac arrest after cardiac surgery.</AbstractText>Data on all cardiac surgical patients who suffered a sudden cardiac arrest during the first 24 h after surgery were collected prospectively. Cardiac arrest was defined as the cessation of cardiac mechanical activity with the absence of a palpable central pulse, apnoea and unresponsiveness, including ventricular fibrillation, asystole and pulseless electrical activity. Forty patients were randomized to either conventional CPR (n = 21) or IAC-CPR (n = 19). IAC-CPR was initially performed by compressing the abdomen midway between the xiphoid and the umbilicus during the relaxation phase of chest compression. If spontaneous circulation was not restored after 10-15 min, the surgical team would immediately proceed to resternotomy. The endpoints of the study were safety, return of spontaneous circulation (ROSC) >5 min, survival to hospital discharge and survival for 6 months.</AbstractText>With IAC-CPR, there were more patients in terms of ROSC, survival to hospital discharge, survival for 6 months and fewer CPR-related injuries compared with patients who underwent conventional CPR.</AbstractText>IAC-CPR is feasible and safe and may be advantageous in cases of cardiac arrest after cardiac surgery.</AbstractText>© The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.</CopyrightInformation> |
11,522 | Acute effects of smoking on QT dispersion in healthy males. | Cigarette smoking increases the risk of ventricular fibrillation and sudden cardiac death (SCD). QT dispersion (QTD) is an important predictor of cardiac arrhythmia. The aim of this study was to assess the acute effect of smoking a single standard cigarette containing 1.7 mg nicotine on QT interval and QTD in healthy smokers and nonsmokers.</AbstractText>The study sample population consisted of 40 healthy male hospital staff, including 20 smokers and 20 nonsmokers. They were asked to refrain from smoking at least 6 h before attending the study. A 12-lead surface electrocardiogram (ECG), recorded at paper speed of 50 mm/s, was obtained from all participants before and 10 min after smoking of a single complete cigarette. QT interval, corrected QT interval, QTD, and corrected QT dispersion (QTcD) were measured before and after smoking.</AbstractText>Smokers and nonsmokers did not have any significant differences in heart rate (HR) (before smoking = 67.35 ± 5.14 vs. 67.70 ± 5.07, after smoking = 76.70 ± 6.50 vs. 76.85 ± 6.50, respectively), QTD (before smoking = 37.75 ± 7.16 vs. 39.15 ± 6.55, after smoking = 44.75 ± 11.97 vs. 45.50 ± 9.58, respectively), and QTcD (before smoking = 39.85 ± 7.40 vs. 41.55 ± 6.57, after smoking = 50.70 ± 14.31 vs. 51.50 ± 11.71, respectively). However, after smoking a single cigarette, HR, mean QTD, and QTcD significantly increased (all had P value <0.001) in comparison to the measures before smoking.</AbstractText>Smoking of a single complete cigarette in both smokers and nonsmokers results in significant QTD increase, which can cause arrhythmia and SCD.</AbstractText> |
11,523 | Establishment of a model of renal impairment with mild renal insufficiency associated with atrial fibrillation in canines. | Chronic kidney disease and occurrence of atrial fibrillation (AF) are closely related. No studies have examined whether renal impairment (RI) without severe renal dysfunction is associated with the occurrence of AF.</AbstractText>Unilateral RI with mild renal insufficiency was induced in beagles by embolization of small branches of the renal artery in the left kidney for 2 weeks using gelatin sponge granules in the model group (n = 5). The sham group (n = 5) underwent the same procedure, except for embolization. Parameters associated with RI and renal function were tested, cardiac electrophysiological parameters, blood pressure, left ventricular pressure, and AF vulnerability were investigated. The activity of the sympathetic nervous system, renin-angiotensin-aldosterone system, inflammation, and oxidative stress were measured. Histological studies associated with atrial interstitial fibrosis were performed.</AbstractText>Embolization of small branches of the renal artery in the left kidney led to ischemic RI with mild renal insufficiency. The following changes occurred after embolization. Heart rate and P wave duration were increased. Blood pressure and left ventricular systolic pressure were elevated. The atrial effective refractory period and antegrade Wenckebach point were shortened. Episodes and duration of AF, as well as atrial and ventricular rate during AF were increased in the model group. Plasma levels of norepinephrine, renin, and aldosterone were increased, angiotensin II and aldosterone levels in atrial tissue were elevated, and atrial interstitial fibrosis was enhanced after 2 weeks of embolization in the model group.</AbstractText>We successfully established a model of RI with mild renal insufficiency in a large animal. We found that RI with mild renal insufficiency was associated with AF in this model.</AbstractText> |
11,524 | Effects of atrioventricular nodal ablation on permanent atrial fibrillation patients with cardiac resynchronization therapy: a systematic review and meta-analysis. | Cardiac resynchronization therapy (CRT) is a well-established therapy for patients with heart failure (HF) and wide QRS configuration, especially for those in sinus rhythm. However, for those with permanent AF, atrioventricular nodal (AVN) ablation use remains under debate. Our objective was to evaluate clinical outcomes and mortality of AVN ablation in HF patients with permanent AF receiving CRT. Electronic publication database and reference lists through October 1, 2013 were searched. Observational cohort studies comparing CRT patients with AF who received either AVN ablation or medical therapy were selected. Outcomes included mortality, CRT nonresponse, changes in left ventricular remodeling, and functional outcomes, such as New York Heart Association (NYHA) functional class, quality of life, and 6-minute hall walk distance. Of 1641 reports identified, 13 studies with 1256 patients were included. Among patients with permanent AF and insufficient biventricular pacing (< 90%), those who had undergone AVN ablation compared to those who did not had numerically lower all-cause mortality (risk ratio [RR]: 0.63, 95% confidence interval [CI]: 0.42 to 0.96, P = 0.03) and significantly lower nonresponse to CRT (RR: 0.41, 95% CI: 0.31 to 0.54, P < 0.00001). Furthermore, AVN ablation was not associated with additional improvements on left ventricular ejection fraction, NYHA functional class, 6-minute hall walking distance, and quality of life. In patients with permanent AF undergoing CRT, AVN ablation tended to reduce mortality potentially and improved clinical response when it was applied to patients with inadequate biventricular pacing (< 90%). Randomized controlled trials are needed to further address the efficacy of AVN ablation among this population. |
11,525 | Myocardial performance index derived from pre-ejection period as a novel and useful predictor of cardiovascular events in atrial fibrillation. | The pre-ejection period-derived myocardial performance index measured from tissue Doppler echocardiography (PEPa-derived MPI) was reported to be associated with left ventricular systolic and diastolic function in atrial fibrillation (AF). However, its relationship with cardiovascular outcomes in AF has never been evaluated. This study sought to examine the ability of PEPa-derived MPI in predicting adverse cardiovascular events in AF patients.</AbstractText>In 196 persistent AF patients, we performed comprehensive echocardiography with measurement of PEPa-derived MPI using index beat method. The index beat was defined as the beat following the nearly equal preceding (RR1) and pre-preceding (RR2) intervals. The cycle length of index beat and RR1 and RR2 must be >500ms and the difference between RR1 and RR2 must be <60ms. Cardiovascular events were defined as cardiovascular death, nonfatal stroke, and hospitalization for heart failure.</AbstractText>In the multivariate analysis, chronic heart failure and increased ratio of transmitral E-wave velocity to early diastolic mitral annulus velocity (E/Ea) and PEPa-derived MPI (per 0.1 increase, hazard ratio, 1.104; 95% confidence interval, 1.032-1.182, p=0.004) were associated with increased cardiovascular events. The addition of PEPa-derived MPI to a Cox model containing chronic heart failure, systolic blood pressure, age, diabetes, prior stroke, left ventricular ejection fraction, and E/Ea provided an additional benefit in prediction of adverse cardiovascular events (p=0.015).</AbstractText>In AF patients, the PEPa-derived MPI was a useful predictor of adverse cardiovascular events and could offer an additional prognostic benefit over conventional clinical and echocardiographic parameters.</AbstractText>Copyright © 2014 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.</CopyrightInformation> |
11,526 | [Pharmacotherapy of cardiac arrhythmias in women--what do we know, do we have a choice?]. | The paper presents basic epidemiological, electrophysiological and therapeutical differences of cardiac arrhythmias depended on gender. Inadequate sinus tachycardia, orthostatic tachycardia syndrome and atrioventricular nodal reentrant tachycardia are more common in women as well as prolongation of QT interval and proarrhythmic phenomenon (especially torsade de pointes). Atrial fibrillation, although significantly less common in women, is more onerous, therapeutic aims are worse to achieve and outcomes are less favourable than in men. European guidelines do not recommend different pharmacological treatement of supraventricular and ventricular arrhythmias in relation to gender. Older antyarrhythmic drugs (beta-adrenolytics, amiodarone, sotalol) and as well as newer ones (dronedarone, ivabradine, vernakalant and ranolazine) seem to have the same influence on arrthythmias both in men and women, althouth their long-term safety may be different and depend on influence on QT interval. The paper presents the state of the art of antiarrhythmic drugs that might be prefered among woman in different clinical situations. |
11,527 | [Ventricular and supraventricular arrhythmias in women]. | There are few gender-related differences in electrophysiology regarding occurrence, clinical symptoms and prognosis of arrhythmias. Women tend to have higher incidence of sinus tachycardia and atrio-ventricular nodal re-entry tachycardia. Atrial fibrillation is more frequent among men, but women have worse prognosis as their mortality is higher, "rhythm control" strategy is less favorable and the thromboembolic risk is greater. Ventricular arrhythmias are less common in women and their significance is smaller. As women have longer QTc interval and torsade de pointes is typical women's arrhythmia, physicians must be very careful ordering QT-elongating drugs. Coronary heart disease (CHD) is seldom background for ventricular tachycardia and women with CHD and arrhythmias have better prognosis than men. Sex hormones play important role in women's electrophysiology. Pregnancy increase risk of supraventricular tachycardia and decrease occurrence of torsade de pointes. |
11,528 | [Genetic arrhythmias and gender]. | Sex differences in the incidence and risk of cardiac arrhythmias are well known. Men have higher incidence of sudden cardiac death, ventricular fibrillation and atrial fibrillation, whereas women are more susceptible to ventricular arrhythmias due to QT prolongation. Sex is one of the most important risk factors of sudden cardiac death in several inherited arrhythmic disorders (male sex in Brugada syndrome and catecholaminergic polymorphic ventricular tachycardia, female sex in long QT syndrome) or disease expression (arrhythmogenic right ventricular cardiomyopathy). Electrophysiological parameters differences between man's and woman's heart are assumed to be a result of genomic (slow) and nongenomic (rapid) pathways.Genomic activity of sex hormones results in higher expression of potassium channels in man's cardiomyocytes. Shorter action potential in men is a substrate for arrhythmias in a mechanism of late afterdepolarization. Longer action potentials in women and higher incidence of LQTS allele transmission to daughters increase a risk of torsade de pointes both in inherited LQTS and in drug-induced QT prolongation. Nongenomic pathway of sex hormones involves transmembrane signal transduction. Antiarrhythmic effect of estrogen which is a calcium antagonist, voltage dependent L- type calcium channels and Na/Ca2+ exchanger inhibitor is the most important rapid electrophysiological hormone effect. |
11,529 | Atrial fibrillation in a healthy adolescent after heavy smoking of contraband cigarettes. | The use of contraband cigarettes is a serious public health problem. We present a case of atrial fibrillation in a healthy adolescent suspected to be caused by smoking contraband cigarettes. A 15-year-old man was admitted to our emergency department experiencing syncope and palpitations. He was a cigarette smoker, but he had never smoked any illicit tobacco products before. He had finished a pack of counterfeit cigarettes (20 pieces) in 1.5 h. His electrocardiogram showed atrial fibrillation with a rapid ventricular response and irregular RR intervals. The patient had no history of alcohol use, surgery, palpitations, hypertension, chronic bronchitis, or any infectious diseases. His atrial fibrillation was converted to a normal sinus rhythm after the cardioversion treatment. Our patient was discharged from the pediatric cardiology service and advised to quit smoking cigarettes, strictly warning against illicit tobacco products. In conclusion, intensive smoking of counterfeit cigarettes may lead to occurrences of atrial fibrillation. |
11,530 | HAS-BLED and CHA₂DS₂-VASc scores as predictors of bleeding and thrombotic risk after continuous-flow ventricular assist device implantation. | HAS-BLED and CHA₂DS₂-VASc scores predict bleeding in patients on anticoagulation and thromboembolic (TE) risk in patients with atrial fibrillation, respectively. We hypothesized that these scores would be predictive of bleeding and TE complications following continuous-flow ventricular assist device (CF-VAD) implantation.</AbstractText>Baseline HAS-BLED and CHA2DS2-VASc scores were retrospectively determined for 173 consecutive patients who underwent HeartMate II CF-VAD implantation at a single center from 2005 to 2011. Forty-three patients had bleeding (24.9%) and 22 had TE (12.7%) events over a 290 patient-year follow-up period. The mean ± SD HAS-BLED scores were 2.7 ± 1.0 and 1.9 ± 1.1 (P < .0001) in patients with and without bleeding, respectively. The CHA₂DS₂-VASc scores were 3.6 ± 1.4 and 2.9 ± 1.5 (P = .03) in patients with and without TE events, respectively. A HAS-BLED score of ≥ 3 was associated with a significantly higher risk of bleeding events compared with a score of <3 (42% vs 15%, respectively; hazard ratio [HR] 3.40, 95% confidence interval [CI] 1.82-6.32; P < .001). A CHA₂DS₂-VASc score of ≥ 3 was associated with a higher risk of TE events compared with a score of <3 (18% vs 4%, respectively; HR 4.02, 95% CI 1.19-13.6; P = .025).</AbstractText>Baseline HAS-BLED and CHA₂DS₂-VASc scores of ≥ 3 conferred significantly higher risks of bleeding and TE, respectively, following HeartMate II implantation.</AbstractText>Copyright © 2014 Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,531 | [In vivo evaluation of magnetic and hydrodynamic suspension centrifugal ventricular assist device]. | To verify the function of magnetic and hydrodynamic suspension centrifugal ventricular assist device in a sheep model.</AbstractText>The device was implanted into left ventricular apex on beating hearts. The outflow graft of each device was anastomosed to descending aorta in 11 animals. Hematologic, biochemical and blood clotting tests before and after surgery were performed. The data of pump functions were collected continuously.</AbstractText>Among them, there were death from ventricular fibrillation (n = 3), acute pulmonary edema (n = 1) and left ventricular thrombus and molar cardiac muscle (n = 5). One animal survived for 75 days and died from bacterial infection after pumping for 59 hours. During assistance for 120 days, the flow rate was 3.0-3.4 L/min. All hematologic and biochemical parameters were within normal ranges in one sheep. The walking sheep wore the controller and lithium battery with a blood pump. Neither mechanical wearing nor thrombus formation was observed for inflow and outflow conduits or pump interior.</AbstractText>The magnetic and hydrodynamic suspension centrifugal ventricular assist device demonstrates excellent hemocompatibility and reliability. And there is a great prospect of clinical success.</AbstractText> |
11,532 | Anti-arrhythmic effect of diosgenin in reperfusion-induced myocardial injury in a rat model: activation of nitric oxide system and mitochondrial KATP channel. | This study was designed to investigate the anti-arrhythmic effect of diosgenin preconditioning in myocardial reperfusion injury in rat, focusing on the involvement of the nitric oxide (NO) system and mitochondrial ATP-dependent potassium (mitoKATP) channels in this scenario. After isolation of the hearts of male Wister rats, the study was conducted in an isolated buffer-perfused heart model. Global ischemia (for 30 min) was induced by interruption of the aortic supply, which was followed by 90-min reperfusion. Throughout the experiment, the electrocardiograms of hearts were monitored using three golden surface electrodes connected to a data acquisition system. Arrhythmias were assessed based on the Lambeth convention and were categorized as number, duration and incidence of ventricular tachycardia (VT), ventricular fibrillation (VF), and premature ventricular complexes (PVC), and arrhythmic score. Additionally, lactate dehydrogenase (LDH) levels in coronary effluent were estimated colorimetrically. Diosgenin pre-administration for 20 min before ischemia reduced the LDH release into the coronary effluent, as compared with control hearts (P < 0.05). In addition, the diosgenin-receiving group showed a lower number of PVC, VT and VF, a reduced duration and incidence of VT and VF, and less severe arrhythmia at reperfusion phase, in comparison with controls. Blocking the mitoKATP channels using 5-hydroxydecanoate as well as inhibiting the NO system through prior administration of L-NAME significantly reduced the positive effects of diosgenin. Our finding showed that pre-administration of diosgenin could provide cardioprotection through anti-arrhythmic effects against ischemia-reperfusion (I/R) injury in isolated rat hearts. In addition, mitoKATP channels and NO system may be the key players in diosgenin-induced cardioprotective mechanisms. |
11,533 | Long-term follow-up of asymptomatic or mildly symptomatic patients with severe degenerative mitral regurgitation and preserved left ventricular function. | The timing for mitral valve surgery in asymptomatic patients with severe mitral regurgitation and preserved left ventricular function remains controversial. We analyzed the immediate and long-term outcomes of these patients after surgery.</AbstractText>From January 1992 to December 2012, 382 consecutive patients with severe chronic degenerative mitral regurgitation, with no or mild symptoms, and preserved left ventricular function (ejection fraction ≥ 60%) were submitted to surgery and followed for up to 22 years (3209 patient-years). Patients with associated surgeries, other than tricuspid valve repair, were excluded. Cox proportional-hazard survival analysis was performed to determine predictors of late mortality and mitral reoperation. Subgroup analysis involved patients with atrial fibrillation or pulmonary hypertension.</AbstractText>Mitral valvuloplasty was performed in 98.2% of cases. Thirty-day mortality was 0.8%. Overall survival at 5, 10, and 20 years was 96.3% ± 1.0%, 89.7% ± 2.0%, and 72.4% ± 5.8%, respectively, and similar to the expected age- and gender-adjusted general population. Patients with atrial fibrillation/pulmonary hypertension had a 2-fold risk of late mortality compared with the remaining patients (hazard ratio, 2.54; 95% confidence interval, 1.17-4.80; P = .018). Benefit was age-dependent only in younger patients (<65 years; P = .016). Patients with atrial fibrillation/pulmonary hypertension (hazard ratio, 4.20, confidence interval, 1.10-11.20; P = .037) and patients with chordal shortening were at increased risk for reoperation, whereas patients with P2 prolapse (hazard ratio, 0.06; confidence interval, 0.008-0.51; P = .037) and patients with myxomatous valves (hazard ratio, 0.072; confidence interval, 0.008-0.624; P = .017) were at decreased risk.</AbstractText>Mitral valve repair can be achieved in the majority of patients with low mortality (<1%) and excellent long-term survival. Patients with atrial fibrillation/pulmonary hypertension had compromised long-term survival, particularly younger patients (aged <65 years), and are at increased risk of mitral reoperation.</AbstractText>Copyright © 2014 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,534 | [Interventional therapy of tachyarrhythmias in the pediatric population]. | Over the past decades, interventional therapy of tachyarrhythmias in children without structural heart disease has evolved as an alternative to chronic pharmacological treatment. Catheter ablation in children over 5 years with symptomatic tachycardia using radiofrequency- or cryoenergy is nowadays performed with high success and low complication rates at experienced centers. The use of modern technologies such as non-fluoroscopic 3-dimensional mapping has further increased efficacy and safety of catheter ablation, and has led to a significant reduction of fluoroscopy time and dose.Arrhythmia substrates treated most frequently by catheter ablation in children include accessory pathways (WPW syndrome) leading to atrioventricular reentrant tachycardia (AVRT) and dual AV nodal pathways causing atrioventricular nodal reentrant tachycardia (AVNRT). Success rates of catheter ablation for these substrates during long-term follow up are over 90 %. Less common forms of tachycardias in children, such as focal atrial tachycardia, ventricular outflow tachycardias or idiopathic left ventricular tachycardia, are also amenable to catheter ablation with good long-term results. In asymptomatic children with preexcitation on the surface ECG (accessory pathway with the risk of rapid antegrade conduction during atrial fibrillation) the indication for catheter ablation of the accessory pathway for the prevention of sudden cardiac death should already be evaluated during childhood. |
11,535 | A shocking complication of a pneumothorax: chest tube-induced arrhythmias and review of the literature. | We describe a patient with a recent chest tube insertion leading to atrial fibrillation with rapid ventricular rate that led to multiple inappropriate internal cardiac defibrillator (ICD) shocks. This is the first reported case of this occurring in a patient with an ICD leading to inappropriate shocks. Our elderly patient with emphysema presented with a spontaneous pneumothorax and developed rapid atrial fibrillation following emergency tube thoracostomy. The patient had a single lead ICD and received multiple inappropriate shocks for the rapid ventricular rate in the therapy zone. Although medical treatment helped stabilize the patient, resolution of the atrial fibrillation occurred only after the chest tube was removed. In a patient with a chest tube or other intrathoracic catheters, maintaining a high index of suspicion that chest tube insertions can cause secondary life threatening cardiovascular complications needs to be considered. In such patients, removal of the device proves to be the most prudent treatment action. |
11,536 | Implantable defibrillators for secondary prevention of sudden cardiac death in cardiac surgery patients with perioperative ventricular arrhythmias. | Randomized studies of implantable cardioverter defibrillators (ICD) have excluded sudden cardiac death survivors who had revascularization before or after an arrhythmic event. To evaluate the role of ICD and the effects of clinical variables including degree of revascularization, we studied cardiac surgery patients who had an ICD implanted for sustained perioperative ventricular arrhythmias.</AbstractText>The electronic database for Southern California Kaiser Foundation hospitals was searched for patients who had cardiac surgery between 1999 and 2005 and an ICD implanted within 3 months of surgery. One hundred sixty-four patients were identified; 93/164 had an ICD for sustained pre- or postoperative ventricular tachycardia or fibrillation requiring resuscitation. Records were reviewed for the following: presenting arrhythmia, ejection fraction, and degree of revascularization. The primary end point was total mortality (TM) and/or appropriate ICD therapy (ICD-T), and secondary end points are TM and ICD-T. During the mean follow up of 49 months, the primary endpoint of TM+ICD-T and individual end points of TM and ICD-T were observed in 52 (56%), 35 (38%), and 28 (30%) patients, respectively, with 55% of TM, and 23% of ICD-T occurring within 2 years of implant. In multivariate risk analysis, none of the following was associated with any of the end points: incomplete revascularization, presenting ventricular arrhythmia, and timing of arrhythmias.</AbstractText>Our data supports the recent guidelines for ICD in this cohort of patients, as the presence of irreversible substrate and triggers of ventricular arrhythmias, cannot be reliably excluded even with complete revascularization. Further studies are needed to understand this complex group of patients.</AbstractText>© 2014 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.</CopyrightInformation> |
11,537 | The impact of heart failure and left ventricular dysfunction in predicting stroke, thromboembolism, and mortality in atrial fibrillation patients: a systematic review. | Atrial fibrillation (AF) is commonly associated with structural heart disease. Although heart failure (HF) has been proposed as a risk factor for stroke, the coexistence of the 2 diseases increases disproportionally the risk of thromboembolic events. Our objective was to conduct a systematic review to assess the effect of HF on the end points of stroke, systemic embolism (SE), or mortality in patients with AF.</AbstractText>A literature search was performed to identify studies that examined stroke/ SE in relation to AF and HF. Overall, 405 articles satisfied the preinclusion criteria.</AbstractText>In studies in which HF was based on a clinical diagnosis, HF independently increased stroke/SE in 5 of 13 studies, conferring 1.6- to 3.1-fold increase in risk. When HF was defined as impaired left ventricular (LV) function on echocardiography, the additive risk was evident in 4 of 6 studies, with 1.7- to 2.6-fold increase in the risk of stroke/SE. The data about HF with preserved ejection fraction were less robust, although a recent presentation with acute decompensated HF increased the risk of stroke/SE, irrespective of ejection fraction.</AbstractText>LV systolic impairment as identified by echocardiography is an independent risk factor for stroke/SE, although the magnitude by which it increases the risk of stroke cannot be precisely quantified. Whether a clinical diagnosis of HF is a significant risk factor remains inconclusive, although when the diagnosis is certain (recent decompensation requiring hospitalization), it does seem to be a significant risk factor irrespective of LV systolic function.</AbstractText>Copyright © 2014 Elsevier HS Journals, Inc. All rights reserved.</CopyrightInformation> |
11,538 | Comparison of the clinical features and outcomes in two age-groups of elderly patients with atrial fibrillation. | Atrial fibrillation (AF) disproportionately affects older adults. However, direct comparison of clinical features, medical therapy, and outcomes in AF patients aged 65-74 and ≥ 75 years is rare. The objective of the present study was to evaluate the differences in clinical characteristics and prognosis in these two age-groups of geriatric patients with AF.</AbstractText>A total of 1,336 individuals aged ≥ 65 years from a Chinese AF registry were assessed in the present study: 570 were in the 65- to 74-year group, and 766 were in the ≥ 75-year group. Multivariable Cox hazards regression was performed to analyze the major adverse cardiac events (MACEs) between groups.</AbstractText>In our population, the older group were more likely to have coronary artery disease, hypertension, previous stroke, cognitive disorder, or chronic obstructive pulmonary disease, and the 65- to 74-year group were more likely to have valvular heart disease, left ventricular systolic dysfunction, or sleep apnea. The older patients had 1.2-fold higher mean CHADS2 (congestive heart failure, hypertension, age ≥ 75 years, diabetes, stroke) scores, but less probability of being prescribed drugs. Compared with those aged 65-74 years, the older group had a higher risk of death (hazard ratio 2.881, 95% confidence interval 1.981-4.189; P<0.001) or MACE (hazard ratio 2.202, 95% confidence interval 1.646-2.945; P<0.001) at the 1-year follow-up. In multivariable Cox analyses, secondary AF diagnosis, a history of chronic obstructive pulmonary disease, and left ventricular systolic dysfunction were independent predictors of MACE in the older group.</AbstractText>Patients aged ≥ 75 years had a worse prognosis than those aged 65-74 years, and were associated with a higher risk of both death and MACE.</AbstractText> |
11,539 | Late-phase thromboembolism after catheter ablation for paroxysmal atrial fibrillation. | The aim of this study was to investigate the incidence and predictors (which have not previously been fully elucidated) of late-phase thromboembolism (TE) after catheter ablation (CA) for paroxysmal atrial fibrillation (AF).</AbstractText>We studied 1,156 consecutive patients (61±10 years; 891 men; CHADS2score, 0.8±1.0) after CA for symptomatic paroxysmal AF and examined the details of late-phase TE. During a follow-up of 49.5±21.9 months (median, 47 months; range, 6-113 months) after CA, 9 patients (0.78%) developed late-phase TE, all of which were ischemic stroke. Of these, 5 patients with AF recurrence experienced cardioembolism; the AF was asymptomatic at recurrence. The remaining 4 without AF recurrence experienced cardioembolism (n=1), small-vessel occlusion (n=1), large-artery atherosclerosis (n=1), and stroke of other determined etiology (n=1). On Kaplan-Meier analysis patients with structural heart disease (P=0.003), AF recurrence after the final CA (P=0.01), prior stroke (P=0.002), CHADS2score ≥2 (P=0.0002), left ventricular ejection fraction <50% (P<0.0001), and spontaneous echo contrast on transesophageal echocardiogram (P=0.0004) had a significantly higher risk of late-phase TE. Multivariate analysis indicated that CHADS2score ≥2 (HR, 4.49; 95% CI: 1.08-22.56; P=0.04) independently predicted late-phase TE.</AbstractText>The incidence of TE was low after CA for paroxysmal AF, but CHADS2score ≥2 independently increased the risk of late-phase TE.</AbstractText> |
11,540 | [Effects of mild hypothermia plus ifenprodil on apoptosis inducing factor translocation after global cerebral ischemia-reperfusion in rats]. | To explore the effects of mild hypothermia combined with ifenprodil on the survival of neuronal and translocation of apoptosis inducing factor (AIF) following global cerebral ischemia-reperfusion to understand the mechanism of combination in cerebral resuscitation.</AbstractText>Eighty male SD rats were randomly divided into 5 groups of sham (I), model (II), ifenprodil (III), mild hypothermia (IV) and ifenprodil plus mild hypothermia (V) (n = 16 each). Group I completed all procedures except for ventricular fibrillation (VF) and cardio pulmonary resuscitation (CPR). For groups II and V, the model of global cerebral ischemia-reperfusion was established and VF induced with transoesophageal cardiac pacing; groups III and V received by an intraperitoneal injection of ifenprodil immediately after reperfusion and other groups had an equal volume of distilled water. Rectal temperature was cooled down to (32 ± 1)°C in groups IV and V by rubbing body surface with ethanol in 10 min after reperfusion and maintained 4 hours continuously while other groups at (37 ± 1)°C. In hippocampal CA1 region at 24 hours after reperfusion, the pathomorphological changes and quantity of pyramidal cells were detected with hematoxylin and eosin staining, nuclear translocation of AIF was shown with immunofluorescence technique and the nuclear expression level of AIF was measured with Western blot.</AbstractText>Compared with group I (75.0 ± 3.2), the number of pyramidal cells decreased in other groups (P < 0.05); compared with group II (36.0 ± 1.2), the number increased in group III (46.8 ± 1.3), IV (49.0 ± 2.7) and V (61.3 ± 2.60) (P < 0.05). In particular, cell count increased significantly in group V (P < 0.05). Compared to group I, the translocation of AIF form mitochondria to nucleus was detected in other groups; compared with group I (0.022 ± 0.003), the expression level of AIF in the nucleus was higher in other groups (P < 0.05). Compared with group II (1.020 ± 0.029) , the expression levels of AIF in groups III (0.870 ± 0.016), IV (0.820 ± 0.050) and V (0.550 ± 0.050) were lower (P < 0.05). And it decreased significantly in group V (P < 0.05).</AbstractText>Mild hypothermia plus ifenprodil may alleviate neuronal damage after global cerebral ischemia/reperfusion injury through mitigating its pro-apoptotic role after AIF translocation.</AbstractText> |
11,541 | Ventricular pre-excitation: symptomatic and asymptomatic children have the same potential risk of sudden cardiac death. | Children and adolescents with ventricular pre-excitation (VPE) are at increased risk for sudden cardiac death (SCD). Although antiarrhythmic therapy and catheter ablation are well established temporary or definitive treatments for patients with Wolff-Parkinson-White (WPW) syndrome, the optimal management of children with asymptomatic VPE remains to be clearly defined. On the basis of the most recent guidelines and recommendations, the aim of this study was to determine the electrophysiological characteristics of young patients with VPE and WPW syndrome to assess and compare their potential risk of SCD.</AbstractText>We retrospectively investigated 124 consecutive young patients with VPE (51 with WPW syndrome and 73 asymptomatic) who underwent transoesophageal electrophysiological study. At baseline, atrioventricular reentrant tachycardia (AVRT) was induced in 13 WPW vs. 10 asymptomatic patients (25.5 vs. 13.7%, P = NS). Atrial fibrillation (AF) was induced in 13 WPW vs. 15 asymptomatic patients (25.5 vs. 20.5%, P = NS). A shortest pre-excited R-R interval (SPERRI) ≤250 ms during AF was found in four WPW vs. six asymptomatic patients (30.8 vs. 40%, P = NS). During isoproterenol infusion or stress testing, AVRT was induced in 31 of 44 WPW vs. 33 of 69 asymptomatic patients (70.4 vs. 47.8%, P = 0.018). Atrial fibrillation was induced in 12 of 44 WPW vs. 21 of 69 asymptomatic patients (27.3 vs. 30.4%, P = NS). A SPERRI ≤ 210 ms was found in 6 of 12 WPW vs. 10 of 21 asymptomatic patients (50 vs. 47.6%, P = NS). No statistically significant correlation was observed between accessory pathway location and symptoms, AVRT/AF inducibility, or mean APERP/SPERRI values.</AbstractText>Children and adolescents with WPW syndrome have a higher rate of AVRT inducibility than asymptomatic patients. However, no differences between the two groups were found in atrial vulnerability and parameters related to the risk of SCD.</AbstractText>Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.</CopyrightInformation> |
11,542 | Diffuse ventricular fibrosis measured by T₁ mapping on cardiac MRI predicts success of catheter ablation for atrial fibrillation. | There is a complex interplay between the atria and ventricles in atrial fibrillation (AF). Cardiac magnetic resonance (CMR) imaging provides detailed tissue characterization, identifying focal ventricular fibrosis with late gadolinium enhancement (ventricular late gadolinium enhancement) and diffuse fibrosis with postcontrast-enhanced T1 mapping. The aim of the present study was to investigate the relationship between postcontrast ventricular T1 relaxation time on CMR and freedom from AF after pulmonary vein isolation.</AbstractText>One hundred three patients undergoing catheter ablation for symptomatic AF (66% paroxysmal AF; age, 58±10 years; left atrial area, 27±7 cm(2)) underwent preprocedure CMR to determine postcontrast ventricular T1 time. Follow-up included clinical review and 7-day Holter monitors at 6 monthly intervals. All patients underwent successful pulmonary vein isolation. At a mean follow-up of 15±7 months, the single procedure success was 74%. Postcontrast ventricular T1 time was significantly shorter in patients with recurrent AF (366±73 ms) versus patients without AF recurrence (428±90 ms; P=0.002). Univariate predictors of AF recurrence included postcontrast ventricular T1 time, AF type (paroxysmal versus persistent), AF duration, and body mass index. After multivariate analysis, ventricular T1 time (P=0.03) and AF duration (P=0.03) were the only independent predictors. Freedom from AF was present in 84% of patients with a postcontrast ventricular T1 time >380 ms versus 56% in patients with a postcontrast ventricular T1 time <380 ms (P=0.002).</AbstractText>A shorter postcontrast ventricular T1 relaxation time on CMR is associated with reduced freedom from AF after catheter ablation. Diffuse ventricular fibrosis as demonstrated by CMR may, in part, explain recurrent AF after AF ablation.</AbstractText>© 2014 American Heart Association, Inc.</CopyrightInformation> |
11,543 | Ranolazine as a promising treatment option for atrial fibrillation: electrophysiologic mechanisms, experimental evidence, and clinical implications. | Currently available agents for pharmacologic management of atrial fibrillation (AF) are limited by their suboptimal efficacy and nonnegligible proarrhythmic risk. Ranolazine (RN) is a novel antianginal agent with increasingly appreciated antiarrhythmic properties that can suppress ventricular and supraventricular arrhythmias including AF. In this review, we describe the electrophysiological properties of RN, focusing on atrial-selective inhibition of a number of ion channels implicated in the development of AF, particularly the sodium current. We further summarize evidence from experimental studies that demonstrate a potent AF-suppressing effect of RN, alone or in combination with other antiarrhythmic drugs. Of clinical relevance, we present growing evidence from preliminary clinical investigations indicating the safety and efficacy of RN for prevention and treatment of AF in various clinical settings including prevention of AF in patients with acute coronary syndromes, prevention and conversion of postoperative AF after surgical coronary revascularization, sinus rhythm maintenance in drug-resistant recurrent AF, and facilitating of electrical or pharmacological cardioversion in cardioversion-resistant patients. While current experimental and clinical evidence points to RN as a potentially promising agent for suppression of AF, well-designed, large-scale trials will be required before RN can be considered for pharmacological treatment of AF in clinical practice. |
11,544 | Ivabradine Versus Beta-Blockers in Patients with Conduction Abnormalities or Left Ventricular Dysfunction Undergoing Cardiac Surgery. | In patients with conduction abnormalities or left ventricle (LV) dysfunction the use of β-blockers for post cardiac surgery rhythm control is difficult and controversial, with a paucity of information about other drugs such ivabradine used postoperatively. The objective of this study was to compare the efficacy and safety of ivabradine versus metoprolol used perioperatively in cardiac surgery patients with conduction abnormalities or LV systolic dysfunction.</AbstractText>This was an open-label, randomized clinical trial enrolling 527 patients with conduction abnormalities or LV systolic dysfunction undergoing coronary artery bypass grafting or valvular replacement, randomized to take ivabradine or metoprolol, or metoprolol plus ivabradine. The primary endpoints were the composites of 30-day mortality, in-hospital atrial fibrillation (AF), in-hospital three-degree atrioventricular block and need for pacing, in-hospital worsening heart failure (HF; safety endpoints), duration of hospital stay and immobilization and the above endpoint plus in-hospital bradycardia, gastrointestinal symptoms, sleep disturbances, cold extremities (efficacy plus safety endpoint).</AbstractText>Heart rate reduction and prevention of postoperative AF or tachyarrhythmia with combined therapy was more effective than with metoprolol or ivabradine alone during the immediate postoperative management of cardiac surgery patients. In the Ivabradine group, the frequency of early postoperative pacing and HF worsening was smaller than in the Metoprolol group and in combined therapy group. The frequency of primary combined endpoint was lower in the combined Ivabradine + Metoprolol group compared with the monotherapy groups.</AbstractText>Considering efficacy and safety, the cardiac rhythm reduction after open heart surgery in patients with conduction abnormalities or LV dysfunction with ivabradine plus metoprolol emerged as the best treatment in this trial.</AbstractText> |
11,545 | Efficacy of dronedarone versus propafenone in the maintenance of sinus rhythm in patients with atrial fibrillation after electrical cardioversion. | Our objective was to compare the efficacy of dronedarone and propafenone in maintaining sinus rhythm in patients with atrial fibrillation (AF) after electrical cardioversion.</AbstractText>In this single-center, open-label, randomized trial, we randomly assigned patients with AF after electrical cardioversion to receive dronedarone 400 mg BID or propafenone 150 mg TID. Follow-up clinical evaluations were conducted at 1, 2, 3, and 6 months of treatment. The primary end point was the time to the first recurrence of AF.</AbstractText>A total of 98 patients were enrolled (79 men; mean age, 59.2 years; n = 49 per group). The median times to first recurrence of AF were 31 days in the dronedarone group and 32 days in the propafenone group (P = 0.715). The median (interquartile range) ventricular rates at first recurrence of AF were 76.5 (67.3-86.5) beats/min in the dronedarone group and 83.0 (71.0-96.0) beats/min in the propafenone group (P = 0.059).</AbstractText>Dronedarone and propafenone had similar efficacies in maintaining sinus rhythm in patients with AF after electrical cardioversion. The ventricular rate at the first recurrence of AF was numerically but not statistically significantly lower in the dronedarone group than in the propafenone group. ClinicalTrials.gov identifier: NCT01991119.</AbstractText>Copyright © 2014 Elsevier HS Journals, Inc. All rights reserved.</CopyrightInformation> |
11,546 | Relationship between post-cardiac arrest myocardial oxidative stress and myocardial dysfunction in the rat. | Reperfusion after resuscitation from cardiac arrest (CA) is an event that increases reactive oxygen species production leading to oxidative stress. More specifically, myocardial oxidative stress may play a role in the severity of post-CA myocardial dysfunction. This study investigated the relationship between myocardial oxidative stress and post-CA myocardial injury and dysfunction in a rat model of CA and cardiopulmonary resuscitation (CPR). Ventricular fibrillation was induced in 26 rats and was untreated for 6 min. CPR, including mechanical chest compression, ventilation, and epinephrine, was then initiated and continued for additional 6 min prior to defibrillations. Resuscitated animals were sacrificed at two h (n = 9), 4 h (n = 6) and 72 h (n = 8) following resuscitation, and plasma collected for assessment of: high sensitivity cardiac troponin T (hs-cTnT), as marker of myocardial injury; isoprostanes (IsoP), as marker of lipid peroxidation; and 8-hydroxyguanosine (8-OHG), as marker of DNA oxidative damage. Hearts were also harvested for measurement of tissue IsoP and 8-OHG. Myocardial function was assessed by echocardiography at the corresponding time points. Additional 8 rats were not subjected to CA and served as baseline controls.</AbstractText>Compared to baseline, left ventricular ejection fraction (LVEF) was reduced at 2 and 4 h following resuscitation (p < 0.01), while it was similar at 72 h. Inversely, plasma hs-cTnT increased, compared to baseline, at 2 and 4 h post-CA (p < 0.01), and then recovered at 72 h. Similarly, plasma and myocardial tissue IsoP and 8-OHG levels increased at 2 and 4 h post-resuscitation (p < 0.01 vs. baseline), while returned to baseline 72 h later. Myocardial IsoP were directly related to hs-cTnT levels (r = 0.760, p < 0.01) and inversely related to LVEF (r = -0.770, p < 0.01). Myocardial 8-OHG were also directly related to hs-cTnT levels (r = 0.409, p < 0.05) and inversely related to LVEF (r = -0.548, p < 0.01).</AbstractText>The present study provides evidence that lipid peroxidation and DNA oxidative damage in myocardial tissue are closely related to myocardial injury and LV dysfunction during the initial hours following CA.</AbstractText> |
11,547 | Effectiveness of aldosterone antagonists for preventing atrial fibrillation after cardiac surgery in patients with systolic heart failure: a retrospective study. | Postoperative atrial fibrillation (POAF) is the most common arrhythmia after cardiac surgery. There exist consistent experimental and clinical data suggesting that aldosterone antagonists (AAs) may exert beneficial effects regarding electrical and structural remodeling in failing myocardium. Recently, eplerenone (EPL) has been found to reduce the incidence of nonsurgical AF when added to guideline-recommended therapy in patients with systolic heart failure. Based on these findings, we primarily aimed to evaluate by retrospective analysis the impact of the two AAs, EPL and spironolactone (SPL), given at standard therapeutic doses in preventing new-onset POAF in patients the majority of which had a preoperative ejection fraction (EF) below 40%. A total of 332 patients (298 men/34 women, mean age 64.3 ± 9 years) without history of AF were included in this analysis; 132 of these patients received long-term EPL or SPL in addition to beta-blockade/statins therapy and 200 patients received neither EPL nor SPL. All patients underwent on-pump coronary artery bypass graft (80%) and/or valvular surgery (20%). In the nonAA group (EF = 35.8 ± 6%) 90/200 patients (45%) had POAF, while in the AA group (EF = 36.2 ± 5%) only 40/132 patients (30.3%) developed POAF (P < 0.01, χ (2) test). Multivariate logistic regression analysis revealed that only AAs and left atrial diameter significantly affected the development of POAF even when adjusted for other clinical variables (P < 0.05). In conclusion, AAs significantly reduced the incidence of POAF when added to standard heart failure therapy in patients undergoing on-pump cardiac surgery. |
11,548 | Exercise-induced arterial hypertension - an independent factor for hypertrophy and a ticking clock for cardiac fatigue or atrial fibrillation in athletes? | Background : Exercise-induced arterial hypertension (EIAH) leads to myocardial hypertrophy and is associated with a poor prognosis. EIAH might be related to the "cardiac fatigue" caused by endurance training. The goal of this study was to examine whether there is any relationship between EIAH and left ventricular hypertrophy in Ironman-triathletes.</AbstractText>We used echocardiography and spiroergometry to determine the left ventricular mass (LVM), the aerobic/anaerobic thresholds and the steady-state blood pressure of 51 healthy male triathletes. The main inclusion criterion was the participation in at least one middle or long distance triathlon.</AbstractText>When comparing triathletes with LVM <220g  and athletes with LVM >220g there was a significant difference between blood pressure values (BP) at the anaerobic threshold (185.2± 21.5 mmHg vs. 198.8 ±22.3 mmHg, p=0.037). The spiroergometric results were: maximum oxygen uptake (relative VO 2max) 57.3 ±7.5ml/min/kg vs. 59.8±9.5ml/min/kg (p=ns). Cut-point analysis for the relationship of BP >170 mmHg at the aerobic threshold and the probability of LVM >220g showed a sensitivity of 95.8%, a specificity of 33.3%, with a positive predictive value of 56.8 %, a good negative predictive value of 90%. The probability of LVM >220g increased with higher BP during exercise (OR: 1.027, 95% CI 1.002-1.052, p= 0.034) or with higher training volume (OR: 1.23, 95% CI 1.04 -1.47, p = 0.019). Echocardiography showed predominantly concentric remodelling, followed by concentric hypertrophy.</AbstractText>Significant left ventricular hypertrophy with LVM >220g is associated with higher arterial blood pressure at the aerobic or anaerobic threshold. The endurance athletes with EIAH may require a therapeutic intervention to at least prevent extensive stiffening of the heart muscle and exercise-induced cardiac fatigue.</AbstractText> |
11,549 | Echocardiographic and clinical response to cardiac resynchronization therapy in heart failure patients with and without previous right ventricular pacing. | Right ventricular pacing (RVp) results in an electrocardiographic left bundle branch block pattern and can lead to heart failure. This study aimed to evaluate echocardiographic and clinical outcomes of heart failure patients with RVp upgraded to cardiac resynchronization therapy (CRT), as they are frequently excluded from multicentre studies.</AbstractText>This observational study assessed 655 consecutive patients with QRS ≥120 ms and left ventricular ejection fraction ≤35%. There were 465 patients without significant previous RVp and 190 with RVp >40%. Echocardiograms were analysed pre-CRT and ∼ 1 year post-CRT. Death and heart failure hospitalizations were analysed using Cox regression, adjusted for baseline characteristics. The RVp patients had smaller end-systolic volume (P = 0.002), were older (P < 0.001), and had more atrial fibrillation (P < 0.001) pre-CRT. Ejection fraction and proportion of ischaemic aetiology were similar. One year following CRT implantation the ejection fraction response was greater in the RVp group (8.3 ± 9 vs. 5.8 ± 9 units, P = 0.005). The RVp patients had an adjusted 33% lower risk of death or heart failure hospitalization [hazard ratio (HR) 0.67 95% confidence interval (CI) 0.51-0.89, P = 0.005], while tending to have an adjusted lower risk of death (HR 0.73 95% CI 0.53-1.01, P = 0.055).</AbstractText>Despite similar ejection fraction pre-CRT, patients upgraded to CRT with previous RVp have smaller end-systolic volume and respond to CRT at least as well as, if not better than, other wide QRS heart failure patients. A greater improvement in ejection fraction and a lower risk of death or heart failure hospitalization when adjusted for baseline characteristics were seen in those with previous RVp.</AbstractText>© 2014 The Authors. European Journal of Heart Failure © 2014 European Society of Cardiology.</CopyrightInformation> |
11,550 | Circadian pattern of fibrillatory events in non-Brugada-type idiopathic ventricular fibrillation with a focus on J waves. | The circadian pattern of ventricular fibrillation (VF) episodes in patients with idiopathic ventricular fibrillation (IVF) is poorly understood.</AbstractText>The purpose of this study was to assess the circadian pattern of VF occurrence in patients with IVF.</AbstractText>Excluding Brugada syndrome and other primary electrical diseases, the circadian pattern of VF occurrence was determined in 64 patients with IVF. The clinical and electrocardiographic characteristics were compared among patients with nocturnal (midnight to 6:00 AM) VF and nonnocturnal VF in relation to J waves. A J wave was defined as either notching or a slur at the QRS terminal >0.1 mV above the isoelectric line in contiguous leads.</AbstractText>The overall distribution pattern of VF occurrence showed 2 peaks at approximately 6:00 AM and around 8:00 PM. Nocturnal VF was observed in 20 patients (31.3%), and J waves were present in 14 of these 20 individuals (70.0%), whereas J waves were less frequent in the 44 nonnocturnal patients with VF: 16 (36.4%) (P = .0117). Among patients with J waves, nocturnal VF was observed in 46.7% with a peak at approximately 4:00 AM. Nocturnal VF was less common in patients without J waves, occurring in only 17.6% (P = .0124). Both the type and location of J waves and the pattern of the ST segment were similar between the nocturnal and nonnocturnal VF groups. J waves were associated with a VF storm and long-term arrhythmia recurrence.</AbstractText>In IVF, the presence of J waves may characterize a higher nocturnal incidence of VF and a higher acute and chronic risk of recurrence.</AbstractText>Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,551 | Footprints of cardiac mechanical activity as expressed in lung Doppler signals. | To determine the diagnostic information contained in cardiac pulsatile pressure waves as expressed in the Doppler signals recorded over the right lung.</AbstractText>The pulsatile characteristics of the pulmonary vascular system were studied by means of the novel pulse Doppler technology in 38 control volunteers, 31 patients with atrial fibrillation (AF) and 7 patients with atrial flutter. The Doppler velocity waveforms recorded were interpreted in relation to the cardiac cycle mechanical events that generate them: Ventricular systole (S), diastole (D) and presystolic left atrial contraction (A). It was demonstrated that in all cases of AF, wave-A was absent. With longer diastole a high frequency velocity waves were visible. It is assumed that they represent the atrial mechanical fibrillation. In the patients with atrial flutter, the single A-wave was replaced by a waveform termed F, the frequency of which exactly matched that of the flutter wave on the ECG. The F-wave had both a positive and negative component.</AbstractText>The lung Doppler signals contain distinct signatures typical of arrhythmias such as AF and atrial flutter that can be used for both diagnosis and to gain insight into the nature of the phenomena.</AbstractText>© 2014, Wiley Periodicals, Inc.</CopyrightInformation> |
11,552 | Severe hypokalemia and thyrotoxic paralysis from painless thyroiditis complicated by life-threatening polymorphic ventricular tachycardia and rhabdomyolysis. | A 61-year-old man presented with lower extremity paralysis and severe hypokalemia. His thyroid function test showed thyrotoxicosis. Despite attempts to correct his hypokalemia, he developed pulseless polymorphic ventricular tachycardia two hours later. He was successfully resuscitated after defibrillation. We performed continuous venovenous hemodiafiltration for 10 days due to acute kidney injury and rhabdomyolysis. We observed life-threatening polymorphic ventricular tachycardia requiring urgent defibrillation, as well as rhabdomyolysis requiring dialysis during the transient thyrotoxic phase of painless thyroiditis. Pay attention to the possibility of the development of life-threatening ventricular tachycardia associated with hypokalemia in the setting of thyroiditis and thyrotoxic paralysis. |
11,553 | Spasm provocation tests performed under medical therapy: a new approach for treating patients with refractory coronary spastic angina on emergency admission. | Objective There are no objective methods for evaluating the severity of vasospasms in patients with refractory coronary spastic angina (R-CSA) under adequate medical therapy. We examined whether spasm provocation tests performed under adequate medication are useful for evaluating the severity of disease in R-CSA patients on emergency admission. Methods and Results We performed spasm provocation tests before and after the administration of medical therapy in eight R-CSA patients, including one ventricular fibrillation survivor (VF-S) and seven patients with unstable angina (UAP) on emergency readmission. We also performed these tests only after medical therapy on urgent admission in four R-CSA patients, including two patients with UAP, one patient with VF-S and one patient with acute coronary syndrome. All 12 R-CSA patients had been medicated with ≥ 2 vasodilator drugs. Positive coronary spasms were defined as >99% transient narrowing. The coronary artery spasms disappeared in three patients under medication, and mitigation of vasospasticity was observed in three patients. In these six cases we continued the same medications. Meanwhile in two patients, we recommended a consultation for psychosomatic medicine. In contrast, the remaining six R-CSA patients exhibited higher levels of vasospasticity, irrespective of the administration of aggressive medical therapy, in which the doses of vasoactive drugs were increased in order to suppress coronary artery spasms. Conclusion In some R-CSA patients on emergency admission, performing spasm provocation tests under medical therapy is useful for determining the subsequent treatment strategy. Therefore, this test may become a new tool in the treatment of R-CSA. |
11,554 | Diurnal and twenty-four hour patterning of human diseases: cardiac, vascular, and respiratory diseases, conditions, and syndromes. | Various medical conditions, disorders, and syndromes exhibit predictable-in-time diurnal and 24 h patterning in the signs, symptoms, and grave nonfatal and fatal events, e.g., respiratory ones of viral and allergic rhinorrhea, reversible (asthma) and non-reversible (bronchitis and emphysema) chronic obstructive pulmonary disease, cystic fibrosis, high altitude pulmonary edema, and decompression sickness; cardiac ones of atrial premature beats and tachycardia, paroxysmal atrial fibrillation, 3rd degree atrial-ventricular block, paroxysmal supraventricular tachycardia, ventricular premature beats, ventricular tachyarrhythmia, symptomatic and non-symptomatic angina pectoris, Prinzmetal vasospastic variant angina, acute (non-fatal and fatal) incidents of myocardial infarction, sudden cardiac arrest, in-bed sudden death syndrome of type-1 diabetes, acute cardiogenic pulmonary edema, and heart failure; vascular and circulatory system ones of hypertension, acute orthostatic postprandial, micturition, and defecation hypotension/syncope, intermittent claudication, venous insufficiency, standing occupation leg edema, arterial and venous branch occlusion of the eye, menopausal hot flash, sickle cell syndrome, abdominal, aortic, and thoracic dissections, pulmonary thromboembolism, and deep venous thrombosis, and cerebrovascular transient ischemic attack and hemorrhagic and ischemic stroke. Knowledge of these temporal patterns not only helps guide patient care but research of their underlying endogenous mechanisms, i.e., circadian and others, and external triggers plus informs the development and application of effective chronopreventive and chronotherapeutic strategies. |
11,555 | Comparison of safety of sotalol versus amiodarone in patients with atrial fibrillation and coronary artery disease. | Sotalol is a commonly prescribed antiarrhythmic drug (AAD) used for maintaining sinus rhythm in patients with atrial fibrillation (AF). Although randomized studies have found that sotalol can significantly delay time to AF recurrence, its association with mortality is less clear, particularly among those with coronary artery disease. We examined outcomes of 2,838 patients with coronary artery disease and AF. Using Cox proportional hazards modeling, landmark analysis, and time-dependent covariates for drug therapy, we compared cumulative survival among patients treated with sotalol (n = 226), amiodarone (n = 856), or no AAD (n = 1,756). Median follow-up was 4.2 years (interquartile range [IQR] 2.0-7.4). The median age was 68 years (IQR 60-75). Compared with those treated with amiodarone or no AAD, patients treated with sotalol were less likely to be black (6% vs 13% vs 13%) and have a previous myocardial infarction (35% vs 51% vs 48%) or a left ventricular ejection fraction <40% (13% vs 26% vs 21%). In follow-up, persistence of sotalol was limited; 97% of patients treated with sotalol were treated for <25% of the follow-up period. In adjusted analysis accounting for time on therapy, sotalol use was associated with an increased risk of all-cause death compared with no drug (hazard ratio 1.53, 95% confidence interval 1.19 to 1.96, p = 0.0009), but a decreased risk of death compared with amiodarone (hazard ratio 0.72, 95% confidence interval 0.55 to 0.91, p = 0.0141). In conclusion, sotalol therapy was more frequently used in patients with fewer co-morbidities, often discontinued early in follow-up, and was associated with increased mortality compared with no AAD but decreased mortality relative to amiodarone. |
11,556 | Three ways to die suddenly: do they all require calcium calmodulin-dependent protein kinase II? | Sudden cardiac death occurs due to a limited number of pathological events. The heart can beat too fast or too slow to maintain adequate cardiac output or the heart can rupture. Here we survey recent evidence that excessive activation of calcium calmodulin-dependent protein kinase II by three core neurohumoral pathways or by oxidant stress can lead to sudden cardiac death due to sinus node dysfunction and bradycardia, ventricular tachycardia or fibrillation, and cardiac rupture. |
11,557 | Impact of denervated myocardium on improving risk stratification for sudden cardiac death. | Between 184,000 and 462,000 Americans die suddenly each year. Fifty percent to 70% of these deaths are due to ventricular tachycardia/fibrillation (VT/VF). We tested whether hibernating myocardium or myocardial sympathetic denervation identifies patients at high-risk for developing VT/VF independently of ejection fraction (EF). Positron emission tomography (PET) was used to quantify myocardial sympathetic denervation ((11)C-meta-hydroxyephedrine [(11)C-HED]), perfusion ((13)N-ammonia), and viability (insulin-stimulated (18)F-2-deoxyglucose [(18)FDG]) in patients with ischemic cardiomyopathy (EF < 35%) eligible for a primary prevention implantable cardioverter defibrillator (ICD). The primary end-point was sudden cardiac arrest (SCA) defined as arrhythmic death or ICD discharge for VT/VF > 240 bpm. Volumes of total denervated (P = .001) and viable denervated myocardium ((11)C-HED-(18)FDG mismatch, P = .03) predicted SCA, whereas hibernating and infarcted myocardium did not. Multivariate analysis identified four independent predictors of SCA: denervated myocardium > 37.6% of left ventricule (LV), LV end-diastolic volume > 98 mL/m(2), creatinine level > 1.49 mg/dL, and no angiotensin- inhibition therapy. Denervated myocardium had a hazard ratio of 3.5 for SCA (10.3%/year vs. 3.0%/year, p=0.001). Absence of all four factors predicted low risk (44% of cohort; SCA <1%/y) whereas two or more factors identified subjects at high-risk (20% of cohort; SCA 12%/y). Denervated myocardium quantified using PET strongly predicts risk of SCA, and is independent of EF, infarct volume, and other clinical variables. |
11,558 | Cardiovascular changes after administration of aerosolized salbutamol in horses: five cases. | Prevention and treatment of intraoperative hypoxemia in horses is difficult and both efficacy and safety of therapeutic maneuvers have to be taken into account. Inhaled salbutamol has been suggested as treatment of hypoxia in horses during general anesthesia, due to safety and ease of the technique. The present report describes the occurrence of clinically relevant unwanted cardiovascular effects (i.e. tachycardia and blood pressure modifications) in 5 horses undergoing general anesthesia in dorsal recumbency after salbutamol inhalation. Balanced anesthesia based on inhalation of isoflurane in oxygen or oxygen and air and continuous rate infusion (CRI) of lidocaine, romifidine, or combination of lidocaine and guaifenesine and ketamine was provided. Supportive measures were necessary to restore normal cardiovascular function in all horses but no long-term adverse effects were noticed in any of the cases. |
11,559 | Awakening and withdrawal of life-sustaining treatment in cardiac arrest survivors treated with therapeutic hypothermia*. | To characterize the prevalence of withdrawal of life-sustaining treatment, as well as the time to awakening, short-term neurologic outcomes, and cause of death in comatose survivors of out-of-hospital resuscitated cardiopulmonary arrests treated with therapeutic hypothermia.</AbstractText>Single center, prospective observational cohort study of consecutive patients with out-of-hospital cardiopulmonary arrests.</AbstractText>Academic tertiary care hospital and level one trauma center in Minneapolis, MN.</AbstractText>Adults with witnessed, nontraumatic, out-of-hospital cardiopulmonary arrests regardless of initial electrocardiographic rhythm with return of spontaneous circulation who were admitted to an ICU.</AbstractText>None.</AbstractText>The study cohort included 154 comatose survivors of witnessed out-of-hospital cardiopulmonary arrests who were admitted to an ICU during the 54-month study period. One hundred eighteen patients (77%) were treated with therapeutic hypothermia. The mean age was 59 years, 104 (68%) were men, and 83 (54%) had an initial rhythm of ventricular tachycardia or fibrillation. Only eight of all 78 patients (10%) who died qualified as brain dead; and 81% of all patients (63 of 78) who died did so after withdrawal of life-sustaining treatment. Twenty of 56 comatose survivors (32%) treated with hypothermia who awoke (as defined by Glasgow Motor Score of 6) and had good neurologic outcomes (defined as Cerebral Performance Category 1-2) did so after 72 hours.</AbstractText>Our study supports delaying prognostication and withdrawal of life-sustaining treatment to beyond 72 hours in cases treated with therapeutic hypothermia. Larger multicenter prospective studies are needed to better define the most appropriate time frame for prognostication in comatose cardiac arrest survivors treated with therapeutic hypothermia. These data are also consistent with the notion that a majority of out-of-hospital cardiopulmonary arrest survivors die after a decision to withdrawal of life-sustaining treatment and that very few of these survivors progress to brain death.</AbstractText> |
11,560 | Left-atrial-appendage occluder migrates in an asymptomatic patient. | Percutaneous closure of the left atrial appendage (LAA) is a new approach to the prevention of cardioembolic events in patients with atrial fibrillation. We implanted an LAA occlusion device (Amplatzer™ Cardiac Plug) in a 70-year-old woman via a transseptal approach. Upon her discharge from the hospital, a transthoracic echocardiogram showed stable anchoring of the device; 6 months after implantation, a routine transthoracic echocardiogram revealed migration of the occluder into the left ventricular outflow tract, in the absence of symptoms. We surgically removed the device from the mitral subvalvular apparatus and closed the LAA with sutures. This case shows that percutaneous LAA occlusion can result in serious adverse events, including device migration in the absence of signs or symptoms; therefore, careful follow-up monitoring is mandatory. |
11,561 | Assessing strategies for heart failure with preserved ejection fraction at the outpatient clinic. | Heart failure with preserved ejection fraction (HFPEF) is the most common form of heart failure (HF), its diagnosis being a challenge to the outpatient clinic practice.</AbstractText>To describe and compare two strategies derived from algorithms of the European Society of Cardiology Diastology Guidelines for the diagnosis of HFPEF.</AbstractText>Cross-sectional study with 166 consecutive ambulatory patients (67.9±11.7 years; 72% of women). The strategies to confirm HFPEF were established according to the European Society of Cardiology Diastology Guidelines criteria. In strategy 1 (S1), tissue Doppler echocardiography (TDE) and electrocardiography (ECG) were used; in strategy 2 (S2), B-type natriuretic peptide (BNP) measurement was included.</AbstractText>In S1, patients were divided into groups based on the E/E'ratio as follows: GI, E/E'> 15 (n = 16; 9%); GII, E/E'8 to 15 (n = 79; 48%); and GIII, E/E'< 8 (n = 71; 43%). HFPEF was confirmed in GI and excluded in GIII. In GII, TDE [left atrial volume index (LAVI) ≥ 40 mL/m2; left ventricular mass index LVMI) > 122 for women and > 149 g/m2 for men] and ECG (atrial fibrillation) parameters were assessed, confirming HFPEF in 33 more patients, adding up to 49 (29%). In S2, patients were divided into three groups based on BNP levels. GI (BNP > 200 pg/mL) consisted of 12 patients, HFPEF being confirmed in all of them. GII (BNP ranging from 100 to 200 pg/mL) consisted of 20 patients with LAVI > 29 mL/m2, or LVMI ≥ 96 g/m2 for women or ≥ 116 g/m2 for men, or E/E'≥ 8 or atrial fibrillation on ECG, and the diagnosis of HFPEF was confirmed in 15. GIII (BNP < 100 pg/mL) consisted of 134 patients, 26 of whom had the diagnosis of HFPEF confirmed when GII parameters were used. Measuring BNP levels in S2 identified 4 more patients (8%) with HFPEF as compared with those identified in S1.</AbstractText>The association of BNP measurement and TDE data is better than the isolated use of those parameters. BNP can be useful in identifying patients whose diagnosis of HF had been previously excluded based only on TDE findings.</AbstractText> |
11,562 | [Evidence-based guidelines for cardio-pulmonary resuscitation in the dog and cat]. | Early recognition of a cardio-pulmonary arrest (CPA) is crucial for patient survival. Every non-breathing and non-responsive patient should be considered to have CPA, and examination of the vital signs should last no longer than 5-10 seconds. If in doubt, effective chest compressions should be started immediately (frequency of 100-120 compressions per minute, compression depth one third to half of the chest diameter, full chest wall recoil between the compressions, no interruption, change of compressing person every 2 minutes). Furthermore, the patient should be intubated and ventilated as early as possible with a frequency of 10 breaths per minute and a volume of 10 ml/kg. Additional measures include monitoring (electrocardiogram, end-expiratory carbon dioxide concentration), placement of an intravenous or intraosseous catheter, administration of opioid-, benzodiazepine- and/or α2-antagonists and ECG-dependent therapy to restore spontaneous circulation. In the case of asystole and pulseless electric activity, epinephrine (0.01 mg/kg every 3-5 minutes, alternative dose concept: 0.1 mg/kg epinephrine) is advised. In the case of CPA due to elevated vagal tonus or bradycardia, atropine should be given (0.04 mg/kg every 3-5 minutes). If ventricular fibrillation or pulseless ventricular tachyarrhythmia is present, defibrillation is the therapy of choice. When this is not possible, amiodarone (5 mg/kg) or lidocaine (2 mg/kg) should be administered. Furthermore, 100% oxygen should be given during resuscitation, while only a few patients benefit from infusion therapy. Following the return of spontaneous circulation, intensive care of the patient is necessary. This involves intense monitoring and support of the haemodynamic situation using intravenous fluids, vasopressors and positive inotropic drugs as well as an improvement of gas exchange and neuroprotection. |
11,563 | Carbon monoxide inhibits inward rectifier potassium channels in cardiomyocytes. | Reperfusion-induced ventricular fibrillation (VF) severely threatens the lives of post-myocardial infarction patients. Carbon monoxide (CO)--produced by haem oxygenase in cardiomyocytes--has been reported to prevent VF through an unknown mechanism of action. Here, we report that CO prolongs action potential duration (APD) by inhibiting a subset of inward-rectifying potassium (Kir) channels. We show that CO blocks Kir2.2 and Kir2.3 but not Kir2.1 channels in both cardiomyocytes and HEK-293 cells transfected with Kir. CO directly inhibits Kir2.3 by interfering with its interaction with the second messenger phosphatidylinositol (4,5)-bisphosphate (PIP2). As the inhibition of Kir2.2 and Kir2.3 by CO prolongs APD in myocytes, cardiac Kir2.2 and Kir2.3 are promising targets for the prevention of reperfusion-induced VF. |
11,564 | Meta-analysis of left ventricular hypertrophy and sustained arrhythmias. | Presence of left ventricular hypertrophy (LVH) has been reported to be associated with supraventricular and ventricular arrhythmias, but the association has not been systematically quantified and evaluated. A systematic search of studies in MEDLINE, EMBASE, CINAHL, Scopus, Web of Science, and Cochrane Central Register of Controlled Trials databases was undertaken through April 2014. Studies reporting on LVH and sustained arrhythmias such as atrial fibrillation and supraventricular tachycardias (SVTs) and ventricular arrhythmias (tachycardia and fibrillation) were identified. Pooled effect estimates were calculated with random-effects models (DerSimonian and Laird). A total of 10 eligible studies with 27,141 patients were included in the analysis. The incidence of SVT in patients with LVH was 11.1% compared with 1.1% among patients without LVH (p<0.001). Patients with LVH had 3.4-fold greater odds of developing SVT (odds ratio 3.39, 95% confidence interval 1.57 to 7.31) than those without LVH, although significant heterogeneity was present (I2=98%). Meta-regression analyses revealed the heterogeneity to have originated from differences in the baseline covariates such as age, male gender, hypertension, and diabetes of the individual studies. The incidence of ventricular arrhythmias was 5.5% compared with 1.2% in patients without LVH (p<0.001). The occurrence of ventricular tachycardia or fibrillation was 2.8-fold greater, in the presence of LVH (odds ratio 2.83, 95% confidence interval 1.78 to 4.51), and there was no significant heterogeneity (I2=9%). Presence of LVH in hypertensive patients is associated with a greater risk of sustained supraventricular/atrial and ventricular arrhythmias, and there is an unmet need for identifying and refining risk stratification for this group. |
11,565 | Impact of pre-procedural cardiopulmonary instability in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention (from the Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction Trial). | Rapid reperfusion with primary percutaneous coronary intervention improves survival in patients with ST-segment elevation myocardial infarction. Preprocedural cardiopulmonary instability and adverse events (IAE) may delay reperfusion time and worsen prognosis. The aim of this study was to evaluate the relation between preprocedural cardiopulmonary IAE, door-to-balloon time (DBT), and outcomes in the Harmonizing Outcomes With Revascularization and Stents in AMI (HORIZONS-AMI) trial. Preprocedural cardiopulmonary IAE included sustained ventricular or supraventricular tachycardia or fibrillation requiring cardioversion or defibrillation, heart block or bradycardia requiring pacemaker implantation, severe hypotension requiring vasopressors or intra-aortic balloon counterpulsation, respiratory failure requiring mechanical ventilation, and cardiopulmonary resuscitation. Three-year outcomes of patients with and without IAE according to DBT were compared. Among 3,602 patients, 159 (4.4%) had ≥1 IAE. DBT did not differ significantly in patients with and without IAE; however, patients with IAE were less likely to have Thrombolysis In Myocardial Infarction (TIMI) grade 3 flow after percutaneous coronary intervention. Mortality at 3 years was significantly higher in patients with versus those without IAE (17.0% vs 6.3%, p<0.0001), and IAE was an independent predictor of mortality, whereas DBT was not. However, a significant interaction was present such that 3-year mortality was reduced in patients with DBT<99 minutes (the median) versus ≥99 minutes to a greater extent in patients with IAE (9.9% vs 20.7%, hazard ratio 0.43, 95% confidence interval 0.16 to 1.16) compared with those without IAE (5.0% vs 7.2%, hazard ratio 0.69, 95% confidence interval 0.50 to 0.95) (p for interaction=0.004). In conclusion, IAE before PCI is an independent predictor of death and identifies a high-risk group in whom faster reperfusion may be particularly important to improve survival. |
11,566 | Combined electrical and global markers of dyssynchrony predict clinical response to cardiac resynchronization therapy. | To assess potential additional value of global left ventricular (LV) dyssynchrony markers in predicting cardiac resynchronization therapy (CRT) response in heart failure (HF) patients.</AbstractText>We included 103 HF patients (mean age 67 ± 12 years, 83% male) who fulfilled the guidelines criteria for CRT treatment. All patients had undergone full clinical assessment, NT-proBNP and echocardiographic examination. Global LV dyssynchrony was assessed using total isovolumic time (t-IVT) and Tei index. On the basis of reduction in the NYHA class after CRT, patients were divided into responders and non-responders.</AbstractText>Prolonged t-IVT [0.878 (range, 0.802-0.962), p = 0.005], long QRS duration [0.978 (range, 0.960-0.996), p = 0.02] and high tricuspid regurgitation pressure drop [1.047 (range, 1.001-1.096), p = 0.046] independently predicted response to CRT. A t-IVT ≥ 11.6 s/min was 67% sensitive and 62% specific (AUC 0.69, p = 0.001) in predicting CRT response. Respective values for a QRS ≥ 151 ms were 66% and 62% (AUC 0.65, p = 0.01). Combining the two variables had higher specificity (88%) in predicting CRT response. In atrial fibrillation (AF) patients, only prolonged t-IVT [0.690 (range, 0.509-0.937), p = 0.03] independently predicted CRT response.</AbstractText>Combining prolonged t-IVT and the conventionally used broad QRS duration has a significantly higher specificity in identifying patients likely to respond to CRT. Moreover, in AF patients, only prolonged t-IVT independently predicted CRT response.</AbstractText> |
11,567 | Impact of out-of-hospital cardiac arrest due to ventricular fibrillation in patients with ST-elevation myocardial infarction admitted for primary percutaneous coronary intervention: Impact of ventricular fibrillation in STEMI patients. | Pre-hospital life-threatening ventricular tachycardia/fibrillation (VT/VF) is relatively common in the acute phase of ST-elevation myocardial infarction (STEMI). We evaluated the prognostic impact of out-of-hospital cardiac arrest (OHCA) due to VT/VF in non-selected patients with STEMI admitted for primary percutaneous coronary intervention (PCI).</AbstractText>Prospective hospital registry was used to collect data of consecutive STEMI patients admitted to our hospital between 2005 and 2010. Patients with OHCA were identified from this registry, and their medical records were reviewed.</AbstractText>During the study period, 4653 patients were admitted with STEMI. Data regarding OHCA due to VT/VF was available in 4643 patients (99.8%). A total of 326 patients (7.0%) had OHCA due to VT/VF. Patients with OHCA were younger (60.3 ± 11.8 vs. 64.1 ± 12.9 year, p<0.001), less often had diabetes (5.2% vs. 12.4%, p<0.001) but more often presented with signs of heart failure (Killip class >1:17.5% vs. 7.7%, p<0.001) and cardiogenic shock (29.6% vs. 2.5%, p<0.001). Coronary angiography was performed in 97.5% of the patients. Coronary angiography and primary PCI were performed equally in both groups. In patients with OHCA, the left main artery (2.3% vs. 1.0%, p=0.04) and LAD (49.2% vs. 41.2%, p=0.01) were more often the culprit artery. In-hospital mortality was significantly higher among patients with OHCA (13.80% vs. 3.4%, p<0.001). However, in patients who were discharged alive from the hospital, the one-year mortality and the combined incidence of death and appropriate ICD therapy were similar in patients with and without OHCA.</AbstractText>In a large non-selected STEMI patient population admitted for primary PCI, OHCA due to VT/VF was associated with higher in-hospital mortality but did not affect the long-term prognosis.</AbstractText>© The European Society of Cardiology 2014.</CopyrightInformation> |
11,568 | Results of catheter ablation of atrial fibrillation in hypertrophied hearts - Comparison between primary and secondary hypertrophy. | Approximately 20-25% of the patients with hypertrophic cardiomyopathy (HCM) develop atrial fibrillation (AF) during the clinical course of the disease, a percentage significantly larger than that of the general population. The purpose of the present study was to report on the procedural results of patients with AF and either primary or secondary left ventricular hypertrophy (LVH).</AbstractText>Twenty-two consecutive HCM patients (55% male, mean age 57±8 years) with symptomatic AF, having undergone AF ablation procedures between September 2009 and July 2012 were compared with respect to procedural outcome and follow-up characteristics with 22 matched controls with secondary cardiac hypertrophy (64% male, 63±10 years) from our prospective AF catheter ablation registry.</AbstractText>Radiofrequency catheter ablation (RFCA) was successful in restoring long-term sinus rhythm in patients with LVH due to HCM and due to secondary etiology. However, patients with HCM needed more RFCA procedures and frequently additional antiarrhythmic drug therapy in order to maintain sinus rhythm.</AbstractText>Copyright © 2014 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.</CopyrightInformation> |
11,569 | If inhibition in the atrioventricular node by ivabradine causes rate-dependent slowing of conduction and reduces ventricular rate during atrial fibrillation. | If channels are functionally expressed in atrioventricular (AV) nodal tissue.</AbstractText>The purpose of this study was to address whether the prototypical If inhibitor, ivabradine, at clinically safe concentrations can slow AV node conduction to reduce ventricular rate (VR) during atrial fibrillation (AF).</AbstractText>Effects of ivabradine (0.1 mg/kg i.v. bolus) were studied in an anesthetized Yorkshire pig (N = 7) model of AF and in isolated guinea pig hearts (N = 7).</AbstractText>Ivabradine reduced heart rate (P = .0001) without affecting mean arterial pressure during sinus rhythm. The agent lengthened PR intervals in a rate-dependent manner (P = .0009) by 14 ± 2.7 ms (P = .003) and 25 ± 3.0 ms (P = .0004) and increased atrial-His (A-H) intervals in a rate-dependent manner (P = .020) by 10 ± 1.7 ms and 17 ± 2.8 ms during pacing at 130 and 180 bpm, respectively (both P = .0008). Similar rate-dependent effects were observed in isolated guinea pig hearts. Ivabradine slowed VR during AF from 240 ± 21 bpm to 211 ± 25 bpm (P = .041). The ivabradine-induced increase in A-H interval was inversely correlated with VR (r = -0.85, P = .03, at 130 bpm; r = -0.95, P = .003, at 180 bpm). QT and HV intervals, AF dominant frequency (8.5 ± 0.9 to 8.7 ± 1.1 Hz, P = NS), mean arterial pressure, and left ventricular dP/dt (1672 ± 222 to 1889 ± 229 mm Hg/s, P = NS) during AF were unaffected.</AbstractText>Ivabradine's rate-dependent increase in A-H interval is highly correlated with VR during AF. As dominant frequency was unaltered, AV node conduction slowing during high nodal activation rates appears to be the main mechanism of ivabradine's VR reduction. If inhibition in the AV node may provide a promising target to slow VR during AF without depression in contractility.</AbstractText>Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,570 | Second coupling interval of nonsustained ventricular tachycardia to distinguish malignant from benign outflow tract ventricular tachycardias. | Idiopathic ventricular tachycardia (VT) originating from the outflow tract (OT) usually is considered a benign condition. In rare cases, patients with OT-VT suffer from syncope or even sudden cardiac death. OT-VT is frequently preceded by nonsustained VT (NSVT).</AbstractText>The purpose of this study was to clarify if the ECG parameters of NSVTs could differentiate malignant from benign OT-VT.</AbstractText>We retrospectively evaluated patients without structural heart disease who had documented OT-NSVT on ECG. ECG parameters were compared between patients with syncope, aborted sudden cardiac death, or ventricular fibrillation (malignant group, n = 36) and patients without syncope (benign group, n = 40).</AbstractText>There were no differences with regard to age and gender between the malignant and benign groups. On analysis of NSVT, the first coupling interval (CI) of NSVT was comparable between the 2 groups (458 ± 87 ms vs 485 ± 95 ms, P = .212). However, the second CI of NSVT beats was significantly shorter in the malignant group (313 ± 58 ms vs 385 ± 83 ms, P < .0001). During 48-month follow-up, the benign group had a significantly lower recurrence of clinical VT than the malignant group (P = .046). The malignant group frequently had more than 1 focus of VT, whereas the benign group showed only a single focus (1.82 vs 1.09, P = .023).</AbstractText>The second CI of NSVT in the malignant group was significantly shorter than that of the benign OT-VT group. Careful measurement of the second CI of NSVT may help identify the malignant form of OT-VT, enabling early treatment to prevent future cardiac events.</AbstractText>Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,571 | Translational research in acute central nervous system injury: lessons learned and the future. | Research to improve outcomes from acute central nervous system (CNS) injury has progressed little, although limited examples (eg, induced hypothermia for out-of-hospital ventricular fibrillation cardiac arrest and birth asphyxia and tissue plasminogen activator for ischemic stroke) have proved that it is possible to favorably alter outcome.</AbstractText>To chronicle the evolution of preclinical research designed to provide therapeutic interventions for acute CNS injury.</AbstractText>Preclinical literature cited by major clinical intervention trials was systematically assessed with respect to fulfillment of fundamental elements of experimental design in current guidelines.</AbstractText>Preclinical studies of acute CNS injury to date have a poor record of adhering to basic tenets of experimental design, including randomization, concealment of treatment allocation, definition of sustained robustness of therapeutic benefit, and emulation of clinical disease. Major clinical trials continue to be justified and conducted on the basis of weak preclinical evidence. Publication of preclinical research guidelines and endorsement by scientific journals have been insufficient to alter practice. Novel approaches to preclinical therapeutic development, including multicenter phase 3 trials and preclinical trial registries that document a priori experimental design and primary dependent variables, may overcome this intransigence and enhance possibility for therapeutic breakthroughs.</AbstractText>Current knowledge of acute CNS injury dictates that therapeutic discovery and translation apply known tenets of sound experimental design and emulation of the clinical disorder targeted for therapeutic intervention. Peer-review systems must demand these qualities in proposed and published research to assess validity and potential for clinical translation.</AbstractText> |
11,572 | Outcomes following out-of-hospital cardiac arrest with an initial cardiac rhythm of asystole or pulseless electrical activity in Victoria, Australia. | While internationally reported survival from out-of-hospital cardiac arrest (OHCA) is improving, much of the increase is being observed in patients presenting to emergency medical services (EMS) in shockable rhythms. The purpose of this study was to assess survival and 12-month functional recovery in patients presenting to EMS in asystole or pulseless electrical activity (PEA).</AbstractText>The Victorian Ambulance Cardiac Arrest Registry was searched for adult OHCA patients presenting in non-shockable rhythms in Victoria, Australia between 1st July 2003 and 30th June 2013. We excluded patients defibrillated prior to EMS arrival and arrests witnessed by EMS. Twelve-month quality-of-life interviews were conducted on survivors who arrested between 1st January 2010 and 31st December 2012. The main outcome measures were survival to hospital discharge and 12-month functional recovery measured by the Extended Glasgow Outcome Scale (GOSE).</AbstractText>A total of 38,378 non-shockable OHCA attended by EMS were included, of which 88.0% were asystole and 11.6% were PEA. Of the patients receiving resuscitation, survival to hospital discharge was 1.1% for asystole and 5.9% for PEA (p<0.001), with no significant improvement observed over the 10 year study period. In survivors with 12-month follow-up data, the combined rate of death, vegetative state or lower severe disability was 66.7% (95% CI 41.0-80.0%) for asystole and 44.7% (95% CI 30.2-59.9%) for PEA.</AbstractText>Survival outcomes following OHCA with initial rhythms of asystole or PEA did not improve over the 10-year study period. Our findings indicate high rates of death within 12 months, and unfavourable functional recovery for survivors.</AbstractText>Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
11,573 | Artemisinin prevents electric remodeling following myocardial infarction possibly by upregulating the expression of connexin 43. | Artemisinin has been demonstrated to exert beneficial effects on ventricular remodeling. The present study investigated whether artemisinin was able to decrease the ventricular fibrillation threshold (VFT) in rats following myocardial infarction (MI) and aimed to determine the possible underlying mechanisms. The rats were subjected to surgery to induce MI by ligation of the left anterior descending artery and were randomly allocated to receive vehicle or artemisinin (75 mg/kg/day) treatment for four weeks. Programmed electrical stimulation demonstrated a significantly increased VFT in the artemisinin-treated group compared with the vehicle-treated group. The electrophysiological improvement of the VFT was accompanied by increased immunofluorescence-stained connexin 43 (Cx43), myocardial Cx43 protein and mRNA levels in artemisinin-treated rats. The present study also demonstrated that artemisinin significantly decreased tissue tumor necrosis factor (TNF)-α levels at the infarcted border zone. Thus, artemisinin demonstrated a protective effect on ventricular arrhythmias following MI. Although the precise mechanism by which artemisinin modulates the dephosphorylation of Cx43 is unknown, it is likely that artemisinin increased the expression of Cx43 via the inhibition of TNF-α. |
11,574 | Right ventricular dysfunction predisposes to inducible ventricular tachycardia at electrophysiology studies in patients with acute ST-segment-elevation myocardial infarction and reduced left ventricular ejection fraction. | Inducible ventricular tachycardia (VT) is a strong predictor of spontaneous ventricular tachyarrhythmia following ST-segment-elevation myocardial infarction. Reduced left ventricular ejection fraction (EF) predisposes patients to inducible VT after ST-segment-elevation myocardial infarction. However, the role of right ventricular (RV) dysfunction in predisposing to inducible VT has not been described previously.</AbstractText>Consecutive patients with ST-segment-elevation myocardial infarction treated with primary percutaneous coronary intervention underwent predischarge radionuclide gated heart pool scan to assess ventricular EF. The study cohort included patients with reduced left ventricular EF (left ventricular EF ≤40%) who underwent electrophysiology study (n=220) in an attempt to induce VT. We defined RV dysfunction as RVEF ≤35%. The end point was sustained monomorphic VT (cycle length ≥200 ms). This was considered a positive study. No inducible arrhythmia, ventricular fibrillation, or flutter (cycle length <200 ms) was considered a negative study. Infarct region, infarct-related artery, male sex, and RVEF ≤35% were univariable predictors of positive test. After multivariable analysis, RVEF ≤35% had the strongest association as an independent predictor of inducible VT at electrophysiology study (P<0.001; odds ratio, 5.8; 95% confidence interval, 3.005-11.262).</AbstractText>RV dysfunction (RVEF ≤35%) predisposed to inducible VT at electrophysiology study in patients with impaired left ventricular EF (≤40%) after acute ST-segment-elevation myocardial infarction treated with primary percutaneous coronary intervention.</AbstractText>© 2014 American Heart Association, Inc.</CopyrightInformation> |
11,575 | The NO Regular Defibrillation testing In Cardioverter Defibrillator Implantation (NORDIC ICD) trial: concept and design of a randomized, controlled trial of intra-operative defibrillation testing during de novo defibrillator implantation. | Although defibrillation (DF) testing is still considered a standard procedure during implantable cardioverter-defibrillator (ICD) insertion and has been an essential element of all trials that demonstrated the survival benefit of ICD therapy, there are no large randomized clinical trials demonstrating that DF testing improves clinical outcome and if the outcome would remain the same by omitting DF testing.</AbstractText>Between February 2011 and July 2013, we randomly assigned 1077 patients to ICD implantation with (n = 540) or without (n = 537) DF testing. The intra-operative DF testing was standardized across all participating centres. After inducing a fast ventricular tachycardia (VT) with a heart rate ≥240 b.p.m. or ventricular fibrillation (VF) with a low-energy T-wave shock, DF was attempted with an initial 15 J shock. If the shock reversed the VT or VF, DF testing was considered successful and terminated. If unsuccessful, two effective 24 J shocks were administered. If DF was unsuccessful, the system was reconfigured and another DF testing was performed. An ICD shock energy of 40 J had to be programmed in all patients for treatment of spontaneous VT/VF episodes. The primary endpoint was the average efficacy of the first ICD shock for all true VT/VF episodes in each patient during follow-up. The secondary endpoints included the frequency of system revisions, total fluoroscopy, implantation time, procedural serious adverse events, and all-cause, cardiac, and arrhythmic mortality during follow-up. Home Monitoring was used in all patients to continuously monitor the system integrity, device programming and performance.</AbstractText>The NO Regular Defibrillation testing In Cardioverter Defibrillator Implantation (NORDIC ICD) trial is one of two large prospective randomized trials assessing the effect of DF testing omission during ICD implantation.</AbstractText>NCT01282918.</AbstractText>Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.</CopyrightInformation> |
11,576 | Evaluation of long-term pituitary functions in patients with severe ventricular arrhythmia: a pilot study. | Traumatic brain injury (TBI), subarachnoid hemorrhage (SAH), stroke and cerebrovascular disease (CVD) are identified as risk factors for hypopituitarism. Pituitary dysfunction after TBI, SAH, and CVD may present in the acute phase or later in the course of the event. Chronic hypopituitarism, particularly growth hormone (GH) deficiency is related to the increased cardiovascular morbidity and mortality. In patients with serious ventricular arrhythmias, who need cardiopulmonary resuscitation, brain tissue is exposed to short-term severe ischemia and hypoxia. However, there are no data in the literature regarding pituitary dysfunction after ventricular arrhythmias.</AbstractText>Forty-four patients with ventricular arrhythmias [ventricular tachycardia (VT), ventricular fibrillation (VF)] (mean age, 55.6 ± 1.8 years; 37 men, 7 women) were included in the study. The patients were evaluated after mean period of 21.2 ± 0.8 months from VT-VF. Basal hormone levels, including serum free triiodothyronine (fT3), free thyroxine (fT4), TSH, ACTH, prolactin, FSH, LH, total testosterone, estradiol, IGF-1, and cortisol levels were measured in all patients. To assess (GH)-insulin like growth factor-1 (IGF-1) axis, glucagon stimulation test was performed and 1 µg ACTH stimulation test was used for assessing hypothalamic-pituitary-adrenal (HPA) axis.</AbstractText>The frequencies of GH, gonadotropin and TSH deficiency were 27.2, 9.0, 2.2%, respectively. Mean IGF-1 levels were lower in GH deficiency group, but it was not statistically significant.</AbstractText>The present preliminary study showed that ventricular arrhythmias may result in hypopituitarism, particularly in growth hormone deficiency. Unrecognized hypopituitarism may be responsible for some of the cardiovascular problems at least in some patients.</AbstractText> |
11,577 | Progressive ventricular dysfunction among nonresponders to cardiac resynchronization therapy: baseline predictors and associated clinical outcomes. | Cardiac resynchronization therapy (CRT) nonresponders have poor outcomes. The significance of progressive ventricular dysfunction among nonresponders remains unclear.</AbstractText>We sought to define predictors of and clinical outcomes associated with progressive ventricular dysfunction despite CRT.</AbstractText>We conducted an analysis of 328 patients undergoing CRT with defibrillator for standard indications. On the basis of 6-month echocardiograms, we classified patients as responders (those with a ≥5% increase in ejection fraction) and progressors (those with a ≥5% decrease in ejection fraction), and all others were defined as nonprogressors. Coprimary end points were 3-year (1) heart failure, left ventricular assist device (LVAD), transplantation, or death and (2) ventricular tachycardia (VT) or ventricular fibrillation (VF).</AbstractText>Multivariable predictors of progressive ventricular dysfunction were aldosterone antagonist use (hazard ratio [HR] 0.23; P = .008), prior valve surgery (HR 3.3; P = .005), and QRS duration (HR 0.98; P = .02). More favorable changes in ventricular function were associated with lower incidences of heart failure, LVAD, transplantation, or death (70% vs 54% vs 33%; P < .0001) and VT or VF (66% vs 38% vs 28%; P = .001) for progressors, nonprogressors, and responders, respectively. After multivariable adjustment, progressors remained at increased risk of heart failure, LVAD, transplantation, or death (HR 2.14; P = .0029) and VT or VF (HR 2.03; P = .046) as compared with nonprogressors. Responders were at decreased risk of heart failure, LVAD, transplantation, or death (HR 0.44; P < .0001) and VT or VF (0.51; P = .015) as compared with nonprogressors.</AbstractText>Patients with progressive deterioration in ventricular function despite CRT represent a high-risk group of nonresponders at increased risk of worsened clinical outcomes.</AbstractText>Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,578 | Left ventricular assist device in the management of refractory electrical storm. | Electrical storm refers to a state of cardiac electrical instability characterized by multiple episodes of ventricular tachycardia (VT) or ventricular fibrillation (VF) within a relatively short period of time and is associated with increased mortality and morbidity. The management of electrical storm involves a variety of strategies, including sedation, anti-arrhythmic and electrolyte replacement as well as revascularization and electrical ablation. However, the management strategy in patients with refractory storm is less clear and may require more invasive approaches. We present a case of severe ventricular tachycardia storm refractory to conservative management that was managed with a HeartMate II left ventricular assist device. |
11,579 | Elevated parathyroid hormone, but not vitamin D deficiency, is associated with increased risk of heart failure in older men with and without cardiovascular disease. | Hyperparathyroidism and low vitamin D status have been implicated in the pathogenesis of heart failure (HF). We examined the prospective associations between parathyroid hormone (PTH), circulating 25-hydroxyvitamin D, and markers of mineral metabolism and risk of incident HF in older men with and without established cardiovascular disease.</AbstractText>Prospective study of 3731 men aged 60 to 79 years with no prevalent HF followed up for a mean period of 13 years, in whom there were 287 incident HF cases. Elevated PTH (≥55.6 pg/mL; top quarter) was associated with significantly higher risk of incident HF after adjustment for lifestyle characteristics, diabetes mellitus, blood lipids, blood pressure, lung function, heart rate, renal dysfunction, atrial fibrillation, forced expiratory volume in 1 second, and C-reactive protein (hazards ratio, 1.66; 95% confidence interval, 1.30-2.13). The increased risk was seen in both men with and without previous myocardial infarction or stroke (hazards ratio, 1.72; 95% confidence interval, 1.07-2.76; hazards ratio, 1.70; 95% confidence interval, 1.25-2.30, respectively). Elevated PTH was significantly associated with N-terminal probrain natriuretic peptide, a marker of left ventricular wall stress. By contrast, 25-hydroxyvitamin D and other markers of mineral metabolism including serum calcium and phosphate showed no significant association with incident HF after adjustment for age.</AbstractText>Elevated PTH, but not 25-hydroxyvitamin D or other markers of mineral metabolism, is associated with increased risk of HF in both older men with and without myocardial infarction/stroke. This increased risk was not explained by its association with known risk factors for HF. Further studies are now needed to elucidate the mechanisms underlying this association.</AbstractText>© 2014 American Heart Association, Inc.</CopyrightInformation> |
11,580 | [Dilated cardiomyopathy caused by p.E446K mutation in SCN5A gene]. | Dilated cardiomyopathy (DCM) is myocardial disorder characterized by progressive heart chambers enlargement and impairment of myocardial contractility. This disorder is the most common cause of advanced heart failure requiring the heart transplantation. The prevalence of the disease is 36.5 per 100 000 in population. About 20-30% of cases are familial. Disease is genetically heterogenous, there more than 100 genes when mutated can give rise a DCM. In 2004, the role of SCN5A gene mutations was shown in origin of DCM with cardiac conduction defects and arrhythmias. In this work we present a clinical case of dilated cardiomyopathy with cardiac arrhythmias and p.E446K mutation in SCN5A gene. We have observed DCM with mild left ventricular hypertrophy, progressive AV block, atrial fibrillation and congenital heart defect (atrium septal defect) in two generations. The congenital heart defect did not co-segregate with SCN5A mutation and DCM. |
11,581 | [Experimental study of the antiarrhythmic properties of zoniporide]. | The antiarrhythmic properties of the Na+/H(+)-exchanger inhibitor zoniporide have been studied in experiments on rats. On the model of 45-min myocardial ischemia followed by 45-min reperfusion, the drug produced a significant (two-fold) decrease in the intensity of post-reperfusion arrhythmias (p < or = 0.05). On the model of 7-min ischemia followed by 5-min reperfusion, zoniporide prevented the development of ventricular fibrillation in 71.43% of cases as compared to control (p < or = 0.05). The drug also increased the threshold of electrical fibrillation by 69.23% and reduced the time to recovery of the heart rhythm by 37.85%. |
11,582 | Recurrent takotsubo syndrome in a patient with myotonic dystrophy 1. | Stress-induced cardiomyopathy (takotsubo-syndrome, TTS) and its recurrence have not been described in myotonic dystrophy-1.</AbstractText>The patient was a 47-year-old female who was suspected to suffer from myotonic dystrophy-1 at 20 years of age, upon the typical clinical presentation and the electrophysiological findings. During weaning from general anesthesia for resectioning of a pelvic tumour she developed ventricular fibrillation, but was successfully resuscitated. During coronary angiography two days later she experienced recurrent QT-prolongation, torsades de pointes, and ventricular fibrillation, but was successfully resuscitated again each time. Echocardiography and electrocardiography were indicative of TTS, which was confirmed by normal findings on echocardiography and electrocardiography two months later. Ten months after the first TTS she developed dyspnea, leg edema, and anginal chest pain. Recurrence of TTS was diagnosed upon a typical electrocardiography and echocardiography findings. Shortly after onset of the second TTS, she unexpectedly died from sepsis.</AbstractText>TTS may also occur in patients with myotonic dystrophy-1 induced by stress from surgery, respiratory insufficiency, or infection. In patients with myotonic dystrophy-1, takotsubo-syndrome may recur and may represent a previously unreported feature of cardiac involvement in myotonic dystrophy-1.</AbstractText> |
11,583 | Critical Care Transthoracic Echocardiography: Atrial Sinus Rhythm During Ventricular Fibrillation. | A 70-year-old man with end-stage heart failure and a continuous-flow left ventricular assist device received repeated electrical discharges from his biventricular implantable cardiac defibrillator. Although the electrocardiogram demonstrated ventricular fibrillation, the patient was awake and in no distress. A focused transthoracic echocardiogram was performed to assess ventricular function revealing simultaneous atrial sinus rhythm and ventricular fibrillation. This clinical scenario highlights a unique clinical finding, the complexity of the care of continuous-flow left ventricular assist device patients, and the challenges of intensivist-performed bedside focused transthoracic echocardiogram. |
11,584 | Myocardial infarction complicated by left ventricular thrombus and fatal thromboembolism following abrupt cessation of dabigatran. | Novel anticoagulants are increasingly utilised in lieu of warfarin to treat non-valvular atrial fibrillation. Their clinical use in other non-FDA approved settings is also increasing. We present a case in which a patient abruptly stopped taking dabigatran due to a small bowel obstruction and shortly thereafter suffered a myocardial infarction complicated by left ventricular thrombosis with fatal embolisation to the superior mesenteric artery. In this context, we discuss the possibility of a rebound phenomenon of hypercoagulability with abrupt cessation of novel anticoagulants. |
11,585 | Outcomes in patients with sustained ventricular tachyarrhythmias occurring within 48 h of acute myocardial infarction: when is ICD appropriate? | Recent guidelines for implantable cardioverter-defibrillator (ICD) use in patients with early ventricular arrhythmia (VA) after acute myocardial infarction (MI) are based on systolic function and revascularization status, yet decision to implant an ICD remains highly subjective. We aimed to determine characteristics, utilization of ICDs, and long-term outcomes of survivors of early VA (<48 h) after acute MI.</AbstractText>We retrospectively analyzed clinical characteristics, ICD therapies, and survival in 128 patients with early VA after acute MI from 2002-12. Patients were classified for appropriateness of ICD implantation, per 2013 Appropriate Use Criteria (AUC). In 128 early VA survivors after MI, older age, female gender, history of coronary artery bypass graft surgery (CABG) or MI, non-ST-elevation MI or ventricular tachycardia (VT) at presentation predicted worse overall survival (all P < 0.05). While left ventricular ejection fraction (LVEF) did not predict mortality (HR = 1; P = 0.86), post-MI ventricular fibrillation (VF) portended a better long-term prognosis than VT (HR = 0.37; P = 0.001). Twenty-six (20%) early VA survivors received ICD, corresponding well with AUC. Implantable cardioverter-defibrillator recipients had lower post-MI LVEF (P = 0.02) and more frequently presented with non-ST-elevation MI (P = 0.007). Over 2.4 years of median follow-up, ICD recipients had a greater mortality rate than non-ICD recipients (42 vs. 17%; P = 0.02). Appropriate and inappropriate ICD discharges were high in ICD recipients.</AbstractText>Early VA survivors after MI receiving ICD due to suspected non-reversible arrhythmogenic substrate have high rates of appropriate ICD therapy and mortality. Our ICD implantation practice corresponds well with the AUC. Sustained monomorphic VT and non-ST-elevation MI at presentation predict increased risk for death. Larger prospective studies are necessary to confirm our findings, such as to provide evidence for future ICD guidelines.</AbstractText>Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.</CopyrightInformation> |
11,586 | Groin hematoma after electrophysiological procedures-incidence and predisposing factors. | We evaluated the incidence and predisposing factors of groin hematomas after electrophysiological (EP) procedures.</AbstractText>Prospective, observational study, enrolling consecutive patients after EP procedures (Atrial fibrillation: n = 151; Supraventricular tachycardia/Diagnostic EP: n = 82; Ventricular tachycardia: n = 18). Patients underwent manual compression for 10 min and 3 h post procedural bed rest. AF ablations were performed with INR 2-3, ACT > 300, and no protamine sulfate. Adhesive pressure dressings (APDs) were used if sheath size ≥ 10F; procedural time > 120 min; and BMI > 30. Patient-reported hematomas were recorded by a telephone follow-up after 2 weeks.</AbstractText>Hematoma developed immediately in 26 patients (10%) and after 14 days significant hematoma was reported in 68 patients (27%). Regression analysis on sex, age, BMI 25, ACT 300, use of APD, sheath size and number, and complicated venous access was not associated with hematoma, either immediately after the procedure or after 14 days. Any hematoma presenting immediately after procedures was associated with patient-reported hematomas after 14 days, odds ratio 18.7 (CI 95%: 5.00-69.8; P < 0.001).</AbstractText>Any hematoma immediately after EP procedures was the sole predictor of patient-reported hematoma after 2 weeks. Initiatives to prevent groin hematoma should focus on the procedure itself as well as post-procedural care.</AbstractText> |
11,587 | Percutaneous mitral heart valve repair--MitraClip. | Mitral regurgitation (MR) is the most common cardiac valvular disease in the United States. Approximately 4 million people have severe MR and roughly 250,000 new diagnoses of MR are made each year. Mitral valve surgery is the only treatment that prevents progression of heart failure and provides sustained symptomatic relief. Mitral valve repair is preferred over replacement for the treatment of MR because of freedom from anticoagulation, reduced long-term morbidity, reduced perioperative mortality, improved survival, and better preservation of left ventricular function compared with valve replacement. A large proportion of patients in need of valve repair or replacement do not undergo such procedures because of a perceived unacceptable perioperative risk. Percutaneous catheter-based methods for valvular pathology that parallel surgical principles for valve repair have been developed over the last few years and have been proposed as an alternate measure in high-risk patients. The MitraClip (Abbott Labs) device is one such therapy and is the subject of this review. |
11,588 | Fragmented QRS and prediction of paroxysmal atrial fibrillation episodes. | Prior studies have demonstrated the relationship between cardiovascular diseases and fragmented QRS (fQRS). fQRS was also associated with ventricular arrhythmias. Our objective was to find out the relationship between fQRS and paroxysmal atrial fibrillation (PAF).</AbstractText>A total of 301 patients without overt structural heart disease were prospectively included in the study. Patients were divided in to 2 groups according to presence of fQRS. Multivariate logistic regression analysis was used to assess the predictive value of fQRS for predicting PAF.</AbstractText>One hundred and three patients had fQRS. Patients with fQRS were older (53±16.8 vs 45.3±17.2, p<0.001), with larger left atrium (LA) (33.2±5.9 vs 30.1±5.9 mm, p=0.001), with thicker interventricular septum (IVS) (10.2±1.9 vs 9.5±2.3 mm, p=0.032), more diabetic (19.8 vs 10.6%, p=0.029) and have more PAF episodes (22.3 vs 4.1%, p<0.001) in comparison with patients without fQRS. fQRS was an independent predictor of detecting PAF episode (odds ratio, 9.69; 95% confidence interval, 2.46-38.15, p=0.001). Hypertension and diabetes mellitus were also predictive.</AbstractText>The presence of fQRS independently predicted PAF episodes in holter monitoring (HM). Further studies are needed to clarify the clinical implications of this finding.</AbstractText> |
11,589 | Self-terminated long-lasting ventricular fibrillation: What is the mechanism? | A 60-year-old woman with dilated cardiomyopathy was referred to our hospital due to recurrent syncope. The electrocardiogram recorded by an implantable loop recorder during a syncopal episode revealed an episode of ventricular fibrillation lasting almost 3 min that terminated spontaneously. A detailed analysis of the rhythm strip showed that the chaotic rhythm became an organized ventricular rhythm with a cycle length of 220 ms for the last 14 s before it terminated. <<b>Learning objective:</b> Ventricular tachyarrhythmias are one of the causes of syncope and have been observed in 1-3% of syncopal patients using an implantable loop recorder (ILR). However, long-lasting ventricular fibrillation (VF) as a cause of syncope is rare in clinical practice, because VF seldom terminates spontaneously. The long-lasting VF became an organized ventricular rhythm, and finally self-terminated as sinus rhythm was restored and this entire sequence of the arrhythmic events was recorded by an ILR.>. |
11,590 | Vagus nerve stimulation initiated late during ischemia, but not reperfusion, exerts cardioprotection via amelioration of cardiac mitochondrial dysfunction. | We previously reported that vagus nerve stimulation (VNS) applied immediately at the onset of cardiac ischemia provides cardioprotection against cardiac ischemic-reperfusion (I/R) injury.</AbstractText>This study aimed to determine whether VNS applied during ischemia or at the onset of reperfusion exerts differential cardioprotection against cardiac I/R injury.</AbstractText>Twenty-eight swine (25-30 kg) were randomized into 4 groups: Control (sham-operated, no VNS), VNS-ischemia (VNS applied during ischemia), VNS-reperfusion (VNS applied during reperfusion), and VNS-ischemia+atropine (VNS applied during ischemia with 1 mg/kg atropine administration). Ischemia was induced by left anterior descending (LAD) coronary artery occlusion for 60 minutes, followed by 120 minutes of reperfusion. VNS was applied either 30 minutes after LAD coronary artery occlusion or at the onset of reperfusion and continued until the end of reperfusion. Cardiac function, infarct size, myocardial levels of connexin 43, cytochrome c, tumor necrosis factor α, and interleukin 4, and cardiac mitochondrial function were determined.</AbstractText>VNS applied 30 minutes after LAD coronary artery occlusion, but not at reperfusion, markedly reduced ventricular fibrillation incidence and infarct size (~59%), improved cardiac function; attenuated cardiac mitochondrial reactive oxygen species production, depolarization, swelling, and cytochrome c release; and increased the amount of phosphorylated connexin 43 and interleukin 4 as compared with the Control group. These beneficial effects of VNS were abolished by atropine.</AbstractText>VNS could provide significant cardioprotective effects even when initiated later during ischemia, but was not effective after reperfusion. These findings indicate the importance of timing of VNS initiation and warrant the potential clinical application of VNS in protecting myocardium at risk of I/R injury.</AbstractText>Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,591 | Benign clinical significance of J-wave pattern (early repolarization) in highly trained athletes. | J wave/QRS slurring (early repolarization) on 12-lead ECG has been associated with increased risk for ventricular fibrillation in the absence of cardiovascular (CV) disease.</AbstractText>The purpose of this study was to assess the prevalence and clinical significance of J wave/QRS slurring in a large population of competitive athletes.</AbstractText>Seven hundred four athletes (436 males [62%], age 25 ± 5 years) free of CV disease who had engaged in 30 different sports were examined. Serial clinical, ECG, and echocardiographic evaluations were available over 1 to 18 years of follow-up (mean 6 ± 4 years).</AbstractText>J wave was found in 102 athletes (14%) and was associated with QRS slurring in 32 (4%). It was found most commonly in anterior, lateral, and inferior leads (n = 73 [72%]), occasionally in lateral leads (n = 26 [25%]), and rarely in inferior leads (n = 3 [3%]). Most of 102 athletes (n = 86 [84%]) also showed ST-segment elevation. J wave/QRS slurring was associated with other training-related ECG changes (ie, increased R/S-wave voltages in 76%) and left ventricular (LV) morphologic remodeling (LV mass 199 ± 48 g vs 188 ± 56 g, P <.05). During follow-up, no athlete with J wave experienced cardiac event or ventricular tachyarrhythmias, or developed structural CV disease.</AbstractText>In athletes, early repolarization pattern usually is associated with other ECG changes, such as increased QRS voltages and ST-segment elevation, as well as LV remodeling, suggesting that it likely represents another benign expression of the physiologic athlete's heart. J wave (early repolarization) is common in highly trained athletes and does not convey risk for adverse cardiac events, including sudden death or tachyarrhythmias.</AbstractText>Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,592 | A novel cardiac ryanodine receptor gene (RyR2) mutation in an athlete with aborted sudden cardiac death: a case of adult-onset catecholaminergic polymorphic ventricular tachycardia. | Sudden cardiac death (SCD) in athletes <35 years of age are mostly due to congenital or acquired cardiac malformations or hypertrophic cardiomyopathy. However, ion channelopathies such as catecholaminergic polymorphic ventricular tachycardia (CPVT) or long-QT syndromes, which are less frequently observed, are also potential pathogenesis of SCD in young athletes. CPVT is an inherited arrhythmia that is induced by physical or emotional stress and may lead to ventricular fibrillation syncope or SCD. Here, we report a case of athlete woman with adult-onset CPVT and aborted SCD who has a novel missense mutation (K4392R) in the cardiac RyR2 gene. |
11,593 | Spectral Doppler of the hepatic veins in pulmonary hypertension. | Pulsed-wave Doppler interrogation of the hepatic veins (HVs) provides a window to right heart hemodynamics and function. Various pathologies that involve the right heart are manifested on the HV Doppler depending on the location and severity of the involvement and its hemodynamic consequences. Pulmonary hypertension (PHTN), a common finding on echocardiographic studies, imparts changes on the HV Doppler that are important to recognize. In this article, we provide a review of the main abnormalities that are encountered on the HV Doppler in patients with PHTN. |
11,594 | Early repolarization is associated with atrial and ventricular tachyarrhythmias in patients with acute ST elevation myocardial infarction undergoing primary percutaneous coronary intervention. | Recent studies found that early repolarization (ER) is significantly more common in survivors of aborted sudden cardiac death. We hypothesized that ER might be more common in patients with ST elevation myocardial infarction (STEMI) who have complications of atrial and ventricular arrhythmias.</AbstractText>This study included 266 patients with acute STEMI undergoing primary percutaneous coronary intervention. Twelve-lead electrocardiograms were analyzed for ER, defined as J-point elevation ≥ 0.1 mV and "notching" and "slurring" of the terminal part of the QRS complex in at least 2 lateral or inferior leads. Acute and late atrial and ventricular arrhythmic events were evaluated.</AbstractText>The ER pattern was observed in 76 patients (28.6%). Atrial arrhythmia [21/76 (27.6%) vs. 22/190 (11.6%), p=0.001] and ventricular arrhythmia [16/76 (21.1%) vs. 16/190 (8.4%), p=0.004] were more frequently complicated in patients with ER than those without during hospitalization. ER was a significant independent predictor of developing atrial (HR=2.682, 95% CI=1.355-5.310, p=0.005) and ventricular arrhythmia (HR=2.936, 95% CI=1.360-6.335, p=0.006). Three patients with ER and ventricular fibrillation expired during hospitalization [3.9% (3/76) vs. 0% (0/190), p=0.023]. However, the presence of ER did not affect the late recurrence of atrial and ventricular arrhythmia.</AbstractText>The ER pattern is commonly observed in patients with STEMI and associated with atrial and ventricular tachyarrhythmia during acute setting.</AbstractText>Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
11,595 | [Right ventricular septal stimulation would produce similar bi-ventricular dyssynchrony as does apical stimulation in patients with normal ejection fraction]. | To determine in patients with normal ejection fraction, undergoing permanent VVI pacing, if medial septal stimulation has lower dyssynchrony than apical stimulation assessed by echocardiography.</AbstractText>A prospective trial, 19 patients>70 years old, scheduled for VVI pacemaker implantation for complete degenerative atrioventricular block, ventricular frequency<50beat per minute and ejection fraction≥45%. Patients with atrial fibrillation, heart failure, left bundle branch block and QRS durations longer than 120milliseconds in surface electrocardiogram with sinus rhythm were excluded. Patients were randomized to apical implantation group A: 47% and septal implantation group B: 53%. Echocardiographic parameters were measured previous to the implant, 48h, 5 and 48 months after implantation.</AbstractText>No patients had diagnosis of ischemic cardiomyopathy or heart failure. Echocardiographic parameters for interventricular dyssynchrony between groups were A: 14.44±19.76msec vs. B: 9±36.45msec; A: 6.11±62.11msec vs. B: 13±38.31msec; A: 77±53.51msec vs. B: 24.29±80.90msec, P=NS). For interventricular dyssynchrony were A: 46.44±19.76msec vs. B: 42.20±29.56msec; A: 45.33±45.67msec vs. B: 29.80±44.66msec; A: 46,38±20 msec vs. B: 21±27.20msec, P=NS) at 48h, 5 and 48 months, respectively.</AbstractText>Apical site of stimulation does not increase ventricular dyssynchrony rate in patients with preserved ejection fraction. Septal stimulation showed decreased trend in interventricular dyssynchrony.</AbstractText>Copyright © 2013 Instituto Nacional de Cardiología Ignacio Chávez. Published by Masson Doyma México S.A. All rights reserved.</CopyrightInformation> |
11,596 | Resuscitation after cardiac arrest in a septic porcine model: adding vasopressin vs epinephrine alone administration. | Vasopressin administration has been tested in cardiac arrest. However it has not been tested when cardiac arrest occurs in certain circumstances, as in sepsis, where it may have a major role. The aim of the study was to investigate survival after cardiac arrest in a septic porcine model compared with healthy animals and to explore the effectiveness of adding vasopressin vs epinephrine alone administration.</AbstractText>Thirty five healthy piglets of both genders were studied. The piglets were randomly assigned into three groups: group A (n = 8), group B (n = 14), group C (n = 13). Animals of groups B and C were given endotoxin to mimic a septic state before arrest. We applied the same resuscitation protocol to all pigs but we replaced the first dose of epinephrine with vasopressin in pigs of group C. Following surgical preparation and 30 min resting period, baseline measurements were recorded. In order to assess tissue oxygenation, we implemented Near Infrared Spectroscopy (NIRS) with the vascular occlusion technique (VOT) in thirteen lipopolysaccharide (LPS)-treated animals, occluding abdominal aorta and inferior vena cava. Afterwards, LPS (100 μg/kg) was infused in a 30 min period to animals of groups B and C and normal saline to group A. New NIRS measurements were obtained again. Subsequently, we provoked ventricular fibrillation (VF). After 3 min of untreated VF, open chest cardiopulmonary resuscitation (CPR) was performed manually. Primary end point was the restoration of spontaneous circulation (ROSC).</AbstractText>The chance of ROSC for the groups A, B and C was 75%, 35.7%, and 30.7% respectively. A significant difference in ROSC was established between septic (group B + C) and non septic piglets (group A) (P = 0.046). Vasopressin administration had no effect in outcome. LPS administration decreased oxygen consumption rate, as assessed by NIRS, in peripheral tissues (22.6 ± 7.2. vs 18.5 ± 7.2, P = 0.07).</AbstractText>Septic piglets have fewer chances to survive after cardiac arrest. No difference in outcome was observed when the first dose of epinephrine was replaced with vasopressin to treat cardiac arrest in the LPS-treated animals.</AbstractText> |
11,597 | Toxic multinodular goiter in a patient with end-stage renal disease and hemodialysis. | The management of symptomatic hyperthyroidism in patients with end stage renal disease (ESRD) is challenging because of altered clearance of medications and iodine with dialysis; moreover, many patients meeting these criteria are medically fragile. A 77-year-old man with type 2 diabetes and ESRD requiring hemodialysis, with dilated cardiomyopathy and paroxysmal atrial fibrillation, was found to have subclinical hyperthyroidism. Over a 2-year period he became clinically hyperthyroid with serum TSH level of <0.05 mIU/L and free T4 level of 4.3 ng/dL, attributed to toxic multinodular goiter. Despite antithyroid medication, he developed rapid ventricular rate from his atrial fibrillation that resulted in decompensated heart failure and multiple hospitalizations. His hyperthyroidism was successfully controlled with high dose methimazole and potassium iodide treatment, which were eventually discontinued after prolonged use. Nearly 6 months off medications, his hyperthyroidism recurred but was readily resolved when methimazole was restarted. Hyperthyroidism in the medically fragile ESRD patient may precipitate emergent conditions. Antithyroid medications are effective and should be considered as primary therapy for the treatment of hyperthyroidism in patients with hemodialysis. Moreover, clinical guidelines for the characterization and management of individuals with ESRD and subclinical hyperthyroidism should be developed. |
11,598 | Papaverine-induced QT interval prolongation and ventricular fibrillation in a patient with a history of drug-induced QT prolongation. | A 64-year-old woman underwent a coronary flow reserve evaluation using intracoronary-administered papaverine into the left anterior descending artery. Her baseline electrocardiogram (ECG) was normal, but toward the end of papaverine administration, the QTU intervals were excessively prolonged and torsade de pointes occurred, leading to ventricular fibrillation. Ten months previously, the patient's ECG showed mildly prolonged QTc (480 ms(1/2)), which normalized after the cessation of bepridil. This case report suggests that a history of drug-induced QT prolongation can be a risk factor for papaverine-induced fatal ventricular arrhythmia. |
11,599 | Klinefelter syndrome with fabry disease--a case of nondisjunction of the X-chromosome with sex-linked recessive mutation. | A 52 year-old male with Klinefelter syndrome presented with chest tightness and rapid atrial fibrillation with hypotension. His echocardiogram demonstrated symmetrical left ventricular hypertrophy with minimal diastolic dysfunction. Subsequent investigations confirmed the diagnosis of Fabry cardiomyopathy. This is the first reported case of Klinefelter syndrome with homozygous sex-linked recessive mutation presenting primarily with cardiac manifestation. |
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