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10,700 | QT interval, general mortality and the role of echocardiographic parameters of left ventricular hypertrophy: Results from the prospective, population-based CARLA study. | There is convincing evidence of an association between the QT interval on electrocardiograms and general mortality. However, results are inconclusive regarding the extent to which this association depends on ventricular mass and size.</AbstractText>Data were obtained from the prospective, population-based CARLA study, with a mean follow-up of 8.8 years, after exclusion of subjects with atrial fibrillation (919 men, 797 women aged 45-83 years remained eligible). Echocardiographic parameters were left ventricular mass index, left ventricular diastolic dimension index, diastolic interventricular septum thickness, diastolic left ventricular posterior wall and the relative left ventricular wall thickness. Heart rate-corrected QT interval (QTc) was measured with standard 12-lead electrocardiograms using the MEANS algorithm. The association between QTc and survival was modelled using Cox-regression models (crude- and covariate-adjusted). Values were standardized by dividing the QTc by the standard deviation. The association between QTc and survival was assessed in terms of tertiles of echocardiographic parameters.</AbstractText>In covariate-adjusted models, QTc was associated with general mortality (hazard ratio (HR): 1.19; 95% confidence interval (CI): 1.03, 1.38). Compared with higher tertiles, subjects in the lowest tertile of left ventricular mass index (HR=1.73, 95% CI: 1.26, 2.36) showed the strongest association with general mortality, which was also true for the lowest tertile of diastolic left ventricular posterior wall thickness (HR=1.49, 95% CI: 1.10, 2.02).</AbstractText>In the general population, the association between QTc and general mortality is strongest in subjects with low left ventricular mass index and diastolic thickness of the left ventricular posterior wall, thus the prognostic value of QTc needs to be interpreted with regard to these echocardiographic parameters.</AbstractText>© The European Society of Cardiology 2015.</CopyrightInformation> |
10,701 | Transcutaneous carbon dioxide monitoring to avoid hypercapnia during complex catheter ablations: a feasibility study. | The aim of this study was to determine if transcutaneous CO(2) monitoring (TCO(2)) is feasible to avoid hypercapnia during complex catheter ablation. Cumulative analgesic and anxiolytic effects during complex catheter ablation can rarely provoke hypoventilation and respiratory complications. End tidal CO(2) monitors have limitations in non-ventilated patients, and frequent arterial blood gas sampling is impractical.</AbstractText>Consecutive patients undergoing catheter ablation for atrial fibrillation (AF) or ventricular tachycardia (VT) received continuous TCO(2) monitoring. Procedural evaluation of TCO(2) was performed concomitantly with point-of-care arterial blood gas testing. Endpoints included PCO(2) protocol feasibility, TCO(2)/PCO(2) agreement, and avoidance of hypercapnia-related procedural complications.</AbstractText>Fifty patients [AF n = 36 (72 %), VT n = 14 (28 %)] underwent catheter ablation (mean 221.7 ± 57.0 min duration, median 41.4 ± 21.1 min fluoroscopy) in which 6.0 ± 2.6 mg midazolam and 449 ± 225.5 mcg of fentanyl were administered. Monitoring protocol implementation was feasible in 50/50 (100 %) cases. Protocol-driven anesthesia consultation avoided an unplanned intubation in 1 case (2 %) and there was only 1 unplanned intubation (2 %) for oxygen desaturation due to heart failure without hypercapnia during a VT ablation (TCO(2)/PCO(2) agreement <5 mmHg). There were no respiratory or pulseless electrical arrests (0 %) in the study. TCO(2) and PCO(2) correlated well (baseline: r = 0.75, p < 0.001; 1 h:r= 0.72, p < 0.001; 2 h: r = 0.55, p = 0.003; 3 h: r = 0.79, p = 0.02). However, desired agreement was lower than expected [baseline: 33/50 (66 %) < 5 mmHg, 48/50 (96 %) <10 mmHg; 1 h: 29/45 (64 %) < 5 mmHg, 39/45 (87 %) < 10 mmHg; 2 h: 14/26 (54 %) < 5 mmHg, 22/26 (85 %) < 10 mmHg; 3 h: 7/11 (64 %) < 5 mmHg, 10/11 (91 %) < 10 mmHg; >3 h: 1/3 (33 %) < 5 mmHg, 2/3 (66 %) < 10 mmHg].</AbstractText>Transcutaneous CO2 monitoring is feasible during complex catheter ablation and correlates with invasively obtained data. However, further development is needed to achieve the desired level of agreement.</AbstractText> |
10,702 | Atrial fibrillation in amyloidotic cardiomyopathy: prevalence, incidence, risk factors and prognostic role. | Although atrial fibrillation (AF) is a known complication of amyloidotic cardiomyopathy (AC), a precise pathophysiological and prognostic characterization is not available. We therefore aimed to assess prevalence, incidence, risk factors and prognostic significance of AF in light-chain (AL), hereditary transthyretin-related (m-ATTR) and non-mutant transthyretin-related (wt-ATTR) AC.</AbstractText>Retrospective study of 262 patients with AC (123 AL, 94 m-ATTR, 45 wt-ATTR) from a single center.</AbstractText>AF prevalence was 15% (AL 9%, m-ATTR 11%, wt-ATTR 40%). During a median follow-up of 1.2 years 11 patients developed AF (2.1% person-years). Age, heart failure (HF), left ventricular (LV) ejection fraction, renal involvement, left atrial size and right atrial pressure were independently associated with AF. AF was associated with incident HF but not with increased mortality. All AF patients were prescribed warfarin and none suffered thromboembolic events.</AbstractText>In AC the prevalence of AF varies widely according to etiology with a mean value of 15% that reaches 40% in wt-ATTR amyloidosis. Age, HF, LV ejection fraction, left atrial size and right atrial pressure were the main independent risk factors, while wall thickness and etiology were not the main independent risk factors. AF does not seem to impact all-cause mortality but was strongly associated with prevalent and incident HF.</AbstractText> |
10,703 | Eligibility for the Subcutaneous Implantable Cardioverter-Defibrillator in Patients With Hypertrophic Cardiomyopathy. | High-risk hypertrophic cardiomyopathy (HCM) patients benefit from the implantable cardioverter defibrillator (ICD). The subcutaneous ICD (S-ICD) may provide comparable protection while avoiding the shortcomings of transvenous (TV) leads. We assessed S-ICD eligibility according to surface ECG screening test in a cohort of high-risk HCM patients.</AbstractText>47 HCM patients (3 S-ICD candidates; 41 TV-ICD patients without pacing indication; and 3 pacemaker-dependent TV-ICD patients) underwent 4 screening protocols: standard (n = 44); exercise (n = 33); continuous pacing (n = 44); alternating paced/spontaneous QRS (n = 41). Of the 44 patients in the standard screening group, 41 (93%) were eligible. Max LV thickness was inversely related to the number of qualifying leads (3 leads: 21 ± 4 mm; 2 leads: 22 ± 6 mm; 1 lead: 25 ± 6 mm; no leads: 28 ± 11 mm; P = 0.07). Of the 33 patients in the exercise group, 5 were ineligible (3 after exercise). Of these, 2 became eligible after moving sternal electrodes from the left to the right parasternal line (eligibility rate: 30/33; 91%). Of the 44 patients in the continuous pacing group, 28 (64%) were eligible, 8 of which with right parasternal electrodes. In the paced/spontaneous QRS group (n = 41), 21 patients (51%) had at least 1 eligible lead during pacing and retained compatibility on the same lead during spontaneous rhythm, 5 of which with right parasternal electrodes.</AbstractText>S-ICD screening failure is low in HCM, provided that patients with severe hypertrophy are carefully evaluated. Exercise test should be performed and right parasternal leads tested. Pacemaker patients display lower eligibility rate.</AbstractText>© 2015 Wiley Periodicals, Inc.</CopyrightInformation> |
10,704 | Right ventricular cardiomyopathy meeting the arrhythmogenic right ventricular dysplasia revised criteria? Don't forget sarcoidosis! | A 53-year-old woman was referred for ventricular fibrillation with resuscitation. A CT-angiography showed signs of a right ventricular enlargement without obvious cause. A cardiac MRI demonstrated a dilated and hypokinetic right ventricle with extensive late gadolinium enhancement. Arrhythmogenic right ventricular dysplasia (ARVD) was suspected according to the "revised ARVD task force criteria". An endomyocardial biopsy was inconclusive. The patient developed purulent pericarditis after epicardial ablation therapy and died of toxic shock syndrome. The post-mortem pathologic examination demonstrated sarcoidosis involving the heart, lungs, and thyroid gland. |
10,705 | Intrathoracic pressure swings induced by simulated obstructive sleep apnoea promote arrhythmias in paroxysmal atrial fibrillation. | There is preliminary evidence for a link between obstructive sleep apnoea (OSA) and arrhythmias such as paroxysmal atrial fibrillation (PAF) and sudden cardiac death but underlying mechanisms remain largely unknown.</AbstractText>In this interventional crossover study, we evaluated whether intrathoracic pressure changes, induced by simulated OSA, trigger premature cardiac beats, and alter measures of ventricular repolarization [QTc and Tpeak-to-Tend (TpTec) intervals] in patients with PAF. 12-Lead-electrocardiograms were recorded continuously in 44 patients, while simulating obstructive apnoea (Mueller manoeuvre, MM), obstructive hypopnoea (inspiration through a threshold load, ITH), end-expiratory central apnoea (AP), and during normal breathing (NB) in randomized order. The prevalence of OSA in these 44 patients was assessed by a sleep study. Atrial premature beats (APBs) occurred more frequently during MM (55% of patients) and ITH (32%), but not during AP (14%), compared with NB (9%) (P < 0.001, P = 0.006 and P = 0.688, respectively). Mueller manoeuvre led to a significant prolongation of QTc and TpTec intervals (+17.3 ms, P < 0.001 and +4.3 ms, P = 0.005). Inspiration through a threshold load significantly increased QTc (+9.6 ms, P < 0.001) but not TpTec. End-expiratory central apnoea did not alter QTc and TpTec intervals. According to the sleep study, 56% of patients had OSA (apnoea hypopnoea index ≥5).</AbstractText>Simulated OSA induces APBs which may be important in patients with PAF, because the majority of episodes of PAF has been shown to be triggered by APBs. Simulated OSA leads to a significant prolongation of ventricular repolarization.</AbstractText>Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.</CopyrightInformation> |
10,706 | Thyrotoxicosis: an under-recognised aetiology. | A 53-year-old woman presented for evaluation of dizziness, shortness of breath and chest pain. She was found to be in atrial fibrillation with rapid ventricular response that was determined to be caused by iodine-induced thyrotoxicosis (from a CT scan with intravenous contrast 2 months prior to presentation). Jod-Basedow syndrome (iodine-induced hyperthyroidism) is infrequently considered as a cause of thyrotoxicosis, even when typical risk factors are present. However, this patient did not have typical risk factors: she did not reside in an iodine deficient area, did not have a prior diagnosis of thyroid disorder or goitre, had never been treated with thyroid medications or medications known to cause thyroid dysfunction and she presented later than is typical with this syndrome (2 months after receiving iodinated contrast). She had complete resolution of hyperthyroidism and atrial fibrillation 2 weeks later with no recurrence over the following 7 months. |
10,707 | Pharmacotherapy for inherited arrhythmia syndromes: mechanistic basis, clinical trial evidence and practical application. | In the absence of structural heart disease, sudden cardiac death is frequently caused by inherited arrhythmia syndromes, such as long QT syndrome, Brugada syndrome and catecholaminergic polymorphic ventricular tachycardia. Managing these conditions often requires a combination of lifestyle modification, pharmacotherapy and less frequently, invasive therapy. Over the past decade, patient management has been greatly enhanced by tailored pharmacotherapy as a result of a deeper appreciation for arrhythmia mechanisms and supportive evidence from multicenter cohort studies. This article reviews current knowledge regarding drug therapy for inherited arrhythmias. Anti-arrhythmic mechanisms and available clinical evidence are highlighted while maintaining a practical perspective on patient management. |
10,708 | Influence of the previous use of β-blockers on the early clinical course of acute coronary syndromes. | Recent studies have recently questioned the current role of β-blockers in myocardial infarction. Our purpose is to analyze the influence of the previous use of β-blockers on the early course of patients admitted because of acute coronary syndrome (ACS). We analyzed the data of 37.359 patients included in the ARIAM-Andalucia Registry. Of them, 7759 (20.8%) were previously receiving β-blockers. BB patients were older, more often female, had more risk factors and vascular disease, and less often had an ST-elevation myocardial infarction. In the unadjusted analysis, BB patients less often had ventricular fibrillation or atrioventricular block, and more often a Killip classification >1, and no difference of in-hospital mortality (5.7 vs 5.6%). After logistic regression analysis and propensity score matching, no differences in complications or mortality (odds ratio 0.997, 95% confidence interval 0.882-1.128) were found in relationship to previous β-blockers. In conclusion, we find that the previous administration of β-blockers is not an independent predictor of the early prognosis of ACS. |
10,709 | Low Circulating Levels of Growth Differentiation Factor-15 Before Coronary Artery Bypass Surgery May Predict Postoperative Atrial Fibrillation. | To assess the role of growth differentiation factor-15 (GDF-15) as a potential new predictor of postoperative atrial fibrillation (POAF) after off-pump (OFP) and on-pump (ONP) coronary artery bypass graft (CABG) surgery.</AbstractText>Prospective, single-center, observational study.</AbstractText>University teaching hospital.</AbstractText>The first 50 patients planned for OFP surgery and the first 50 patients planned for ONP surgery among patients referred for CABG with the following exclusion criteria: age<18 or>80 years, previous atrial fibrillation/flutter, previous treatment with amiodarone, previous cardiac surgery, and emergency surgery.</AbstractText>Included patients were equipped with long-duration (7 days) Holter-ECG monitoring.</AbstractText>POAF was defined as an AF episode lasting>30 seconds. All patients underwent preoperative echocardiography to assess left ventricular ejection fraction and left atrial diameter. GDF-15 levels were assessed after induction of anesthesia and 12 hours after arrival at the intensive care unit. Among the 100 patients, 34 (34%) developed POAF. In Cox multivariate regression analysis, the EuroSCORE, left atrial diameter>45 mm, and low GDF-15 levels at induction were associated independently with the onset of POAF. In contrast, preoperative NT-proBNP levels did not predict POAF. The use of ONP surgery was not associated with a higher incidence of POAF, even though baseline and follow-up characteristics in ONP and OFP patients were identical.</AbstractText>In patients with no history of AF, a low plasma level of GDF-15 before CABG surgery was a strong independent predictor of POAF. Moreover, preoperative plasma GDF-15 levels added an incremental predictive value to classic risk factors of POAF.</AbstractText>Copyright © 2015 Elsevier Inc. All rights reserved.</CopyrightInformation> |
10,710 | Utility of T-wave alternans during night time as a predictor for ventricular fibrillation in patients with Brugada syndrome. | The prognostic value of T-wave alternans (TWA) during the night time in patients with Brugada syndrome (Br-S) remains unknown. We assessed TWA for risk stratification using 24-h multichannel Holter electrocardiogram (24-M-ECG) in Br-S. We enrolled 129 patients with Br-S [grouped according to histories of ventricular fibrillation (VF), n = 16; syncope, n = 10; or no symptoms (asymptomatic), n = 103] and 11 controls. Precordial electrodes were attached to the third (3L-V1, 3L-V2) and fourth (4L-V1, 4L-V2 and 4L-V5) intercostal spaces. We measured the values of maximum TWA (max-TWA) during the night time (12 a.m.-6 a.m.) and the day time (12 p.m.-6 p.m.) and calculated parameters of heart rate variability. Compared to the asymptomatic and control groups, the VF and syncope groups showed significantly greater 3L-V2 max-TWA during the night time. The cutoff value for the 3L-V2 max-TWA during the night time was determined as 20 µV (sensitivity 94 % and specificity 48 %; p = 0.01). Multivariate analysis revealed that 3L-V2 max-TWA during the night time ≥20 µV and previous VF episodes were independent predictors of future VF episodes. During a mean follow-up period of 68 ± 37 months, 16 patients experienced VF episodes. The incidence of VF episodes was the highest during the night time (p < 0.001). The 3L-V2 max-TWA during the night time may be a useful predictor for VF episodes in patients with Br-S. |
10,711 | Primary hypoparathyroidism presenting with heart failure and ventricular fibrillation. | A 24-year-old female presented with sudden heart failure and ventricular fibrillation. A complete work-up suggested the existence of primary hypoparathyroidism in an otherwise previously healthy young woman. Left ventricle enlargement was detected by echocardiography with an ejection fraction of 30%. Electrolyte disorders dominated the laboratory results, with severe hypocalcemia, hypokalemia, hypomagnesemia and other changes, which were corrected with infusion therapy. An improvement of her overall condition prompted a switch from electrolyte infusion therapy to the oral route after the first week of treatment. The patient was discharged under calcium, calcitriol, diuretics and angiotensin-converting-enzyme-inhibitors oral maintenance therapy. Two months after discharge, her ejection fraction remained low (33%), although the end-systolic volume had returned to normal values, and her general status had substantially improved. Within a period of 4 months her cardiac function improved significantly and the follow-up surveillance echocardiography showed an ejection fraction of 53%, with normal left ventricle dimensions. |
10,712 | Increased intraventricular pressures are as harmful as the electrophysiological substrate of heart failure in favoring sustained reentry in the swine heart. | Heart failure (HF) electrophysiological remodeling (HF-ER) often includes the effect of chronically increased intraventricular pressures (IVPs) and promotes ventricular tachycardia/ventricular fibrillation (VT/VF). In addition, acutely increased IVPs have been associated with a higher rate of VT/VF episodes in chronic HF.</AbstractText>We hypothesized that increased IVPs and/or an ionic-imbalanced (acidified), catecholamine-rich (adrenergic) milieu (AA milieu) may contribute as much as HF-ER to the substrate for reentry in HF. We used a porcine model of tachycardiomyopathy and evaluated the individual/combined contributions of (1) increased IVPs, (2) HF-ER, and (3) an AA milieu.</AbstractText>HF-ER was induced in 7 pigs by rapid pacing. Seven pigs were used as controls. Hearts were isolated and Langendorff perfused. Programmed ventricular stimulation was conducted under low or increased IVP and normal/AA milieu (4 combinations). Epicardial optical mapping was used to quantify conduction velocity (CV), action potential duration (APD), and dispersion of repolarization (DoR).</AbstractText>HF-ER decreased CV (-34%; P = .002) and increased APD (11%; P = .024) and DoR (21%; P = .007). Increased IVP amplified DoR (36%; P < .001) and decreased CV (-17%; P = .001) and APD (-8%; P < .001). The AA milieu consistently modified only APD (-9%; P < .001) and led to amplified inter-/intra-subject heterogeneity. Increased IVP similarly raised the odds of inducing sustained VT/VF as the presence of HF-ER (>6-fold).</AbstractText>By magnifying DoR, decreasing CV, and shortening APD, increased IVP was as harmful as HF-ER in favoring the substrate for sustained reentry in this model. The AA milieu contributed to a much lesser extent. Thus, a stricter control of IVP might be postulated as a useful add-on antiarrhythmic strategy in HF.</AbstractText>Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
10,713 | Correction. | In the article by Ristagno et al, “Amplitude Spectrum Area to Guide Defibrillation: A Validation on 1617 Patients With Ventricular Fibrillation,” which was published in the February 3, 2015 issue of the journal (Circulation. 2015;131:478–487. DOI: 10.1161/CIRCULATION AHA.114.010989), the authors wish to report an error in Table V of the online-only Data Supplement. Association of AMSA with defibrillation success was independent of the features of the defibrillators, although the type A and B defibrillators accounted for a significantly higher AUC compared with type C defibrillator. Table V in the online-only Data Supplement has been corrected accordingly. The authors regret this error.( |
10,714 | Acute Renal Injury Induced by Hypersensitivity to Tolvaptan in an Elderly Patient with Congestive Heart Failure. | Tolvaptan (TLV) is a new vasopressin type 2 receptor antagonist effective in patients with heart failure (HF). We herein describe the case of an 84-year-old woman who developed acute renal injury induced by hypersensitivity to TLV. The patient had received an implanted pacemaker and was diagnosed with exacerbation of chronic HF due to atrial fibrillation, mitral regurgitation, tricuspid regurgitation and left ventricular dyssynchrony. Treatment with tolvaptan increased the urine volume, improved the dyspnea and decreased the edema. However, the patient's renal function and hyperkalemia worsened, and the blood eosinophil count increased without signs of dehydration or hypotension. Positive findings on a drug-induced lymphocyte stimulation test for TLV were consistent with this diagnosis. |
10,715 | Frequency characteristics and associations with the defibrillation threshold of ventricular fibrillation in patients with implantable cardioverter defibrillators. | The dominant frequency (DF) in frequency analyses is considered to represent the objective cycle length and complexity of activation under conditions of ventricular fibrillation (VF). However, knowledge regarding the mechanisms determining the DF in human VF is limited. We studied the characteristics of the DF of human VF and relationship between DF and the defibrillation threshold.</AbstractText>Seventy-two implantable cardioverter-defibrillator patients and 211 VF were studied. Using defibrillation tests, we performed a frequency analysis with fast Fourier transformation. The correlations between DF and clinical characteristics, including the defibrillation threshold, were assessed.</AbstractText>The mean DF of all induced VFs was 5.2±0.8 Hz. The patients were divided into two groups according to DF: the low-DF (DF <5.2 Hz, n=32) and high-DF (DF ≥5.2 Hz, n=40) groups. The frequency of structural heart disease was significantly higher in the low-DF group. In addition, the QRS duration, QT interval and effective refractory period of the right ventricle (RV-ERP) were significantly longer in the low-DF group. A multivariate analysis showed RV-ERP to be the only independent predictor of DF. Excluding patients receiving group III anti-arrhythmic drugs, which are known to have potent defibrillation threshold effects, the defibrillation threshold was significantly lower in the low-DF group (p=0.026).</AbstractText>We found that the DF of human VF is associated with underlying heart disease, the cardiac function, cardiac conduction, ventricular refractoriness and defibrillation threshold. Our findings may be useful for identifying and managing patients with a high defibrillation threshold.</AbstractText> |
10,716 | Experimental Study of the Effects of EIPA, Losartan, and BQ-123 on Electrophysiological Changes Induced by Myocardial Stretch. | Mechanical response to myocardial stretch has been explained by various mechanisms, which include Na(+)/H(+) exchanger activation by autocrine-paracrine system activity. Drug-induced changes were analyzed to investigate the role of these mechanisms in the electrophysiological responses to acute myocardial stretch.</AbstractText>Multiple epicardial electrodes and mapping techniques were used to analyze changes in ventricular fibrillation induced by acute myocardial stretch in isolated perfused rabbit hearts. Four series were studied: control (n = 9); during perfusion with the angiotensin receptor blocker losartan (1 μM, n = 8); during perfusion with the endothelin A receptor blocker BQ-123 (0.1 μM, n = 9), and during perfusion with the Na(+)/H(+) exchanger inhibitor EIPA (5-[N-ethyl-N-isopropyl]-amiloride) (1 μM, n = 9).</AbstractText>EIPA attenuated the increase in the dominant frequency of stretch-induced fibrillation (control=40.4%; losartan=36% [not significant]; BQ-123=46% [not significant]; and EIPA=22% [P<.001]). During stretch, the activation maps were less complex (P<.0001) and the spectral concentration of the arrhythmia was greater (greater regularity) in the EIPA series: control=18 (3%); EIPA = 26 (9%) (P < .02); losartan=18 (5%) (not significant); and BQ-123=18 (4%) (not significant).</AbstractText>The Na(+)/H(+) exchanger inhibitor EIPA attenuated the electrophysiological effects responsible for the acceleration and increased complexity of ventricular fibrillation induced by acute myocardial stretch. The angiotensin II receptor antagonist losartan and the endothelin A receptor blocker BQ-123 did not modify these effects.</AbstractText>Copyright © 2014 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.</CopyrightInformation> |
10,717 | Behavioral influences on cardiac arrhythmias. | Stress can trigger both ventricular and atrial arrhythmias, as evidenced by epidemiological, clinical, and laboratory studies, through its impact on autonomic activity. Chronic stress also increases vulnerability to arrhythmias. Novel therapies aimed at decreasing the psychological and physiological response to stress may decrease arrhythmia frequency and improve quality of life. |
10,718 | Low left atrial appendage flow velocity predicts recurrence of atrial fibrillation after catheter ablation of persistent atrial fibrillation. | Recurrence after catheter ablation of persistent atrial fibrillation (AF) remains an unsolved issue. This study aimed to explore the association between the left atrial appendage peak flow velocity (LAAV) and AF recurrence after ablation in persistent AF patients.</AbstractText>Fifty-three consecutive patients who underwent an initial catheter ablation of persistent AF were enrolled [age, 65±10 years; male, 42 (79%)]. The LAAV was obtained by transesophageal echocardiography before ablation. All the patients underwent pulmonary vein isolation and were followed up for 12 months. The LAAV and other clinical factors (AF duration, CHA2DS2VASc score, left atrial diameter, left atrial volume, and left ventricular ejection fraction) were tested using a Cox proportional hazards regression analysis as predictors of AF recurrence during the 1-year follow-up.</AbstractText>AF recurrence occurred in 16 (30%) patients. The patients with AF recurrences had lower LAAVs (23.3±7.2cm/s vs. 33.3±15.1cm/s, p=0.002) than those without AF recurrence. In the multivariable analysis, a low LAAV independently predicted AF recurrence (hazard ratio, 3.04; 95% confidence interval, 1.05-8.79; p=0.040). A Kaplan-Meier analysis also demonstrated a lower survival rate free from AF recurrence in the low LAAV group than in the high LAAV group (p=0.030).</AbstractText>A low LAAV was associated with AF recurrence after the initial catheter ablation of persistent AF.</AbstractText>Copyright © 2015. Published by Elsevier Ltd.</CopyrightInformation> |
10,719 | Full-Body MRI in Patients With an Implantable Cardioverter-Defibrillator: Primary Results of a Randomized Study. | Magnetic resonance imaging (MRI) of patients with conventional implantable cardioverter-defibrillators (ICD) is contraindicated.</AbstractText>This multicenter, randomized trial evaluated safety and efficacy of a novel ICD system specially designed for full-body MRI without restrictions on heart rate or pacing dependency. The primary safety objective was >90% freedom from MRI-related events composite endpoint within 30 days post-MRI. The primary efficacy endpoints were ventricular pacing capture threshold and ventricular sensing amplitude.</AbstractText>Subjects received either a single- or dual-chamber ICD. In a 2:1 randomization, subjects either underwent MRI at 1.5-T of the chest, cervical, and head regions to maximize radiofrequency exposure up to 2 W/kg specific absorption rate and gradient field exposure to 200 T/m/s per axis (MRI group, n = 175), or they underwent a 1-h waiting period without MRI (control group, n = 88). A subset of MRI patients underwent ventricular fibrillation induction testing post-MRI to characterize defibrillation function.</AbstractText>In 42 centers, 275 patients were enrolled (76% male, age 60.4 ± 13.8 years). The safety endpoint was met with 100% freedom from the composite endpoint (p < 0.0001). Both efficacy endpoints were met with minimal differences in the proportion of MRI and control patients who demonstrated a ≤0.5 V increase in ventricular pacing capture threshold (100% MRI vs. 98.8% control, noninferiority p < 0.0001) or a ≤50% decrease in R-wave amplitude (99.3% MRI vs. 98.8% control, noninferiority p = 0.0001). A total of 34 ventricular tachyarrhythmia/ventricular fibrillation episodes (20 induced; 14 spontaneous) occurred in 24 subjects post-MRI, with no observed effect on sensing, detection, or treatment.</AbstractText>This is the first randomized clinical study of an ICD system designed for full-body MRI at 1.5-T. These data support that the system is safe and the MRI scan does not adversely affect electrical performance or efficacy. (Confirmatory Clinical Trial of the Evera MRI System for Conditionally-Safe MRI Access; NCT02117414).</AbstractText>Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
10,720 | Cardiac arrest: the changing incidence of ventricular fibrillation. | There are more than 300,000 out-of-hospital cardiac arrests (OHCA) in the USA annually, which can be grouped into those presenting with tachyarrhythmic (shockable) rhythms and those presenting with non-tachyarrhythmic rhythms. The incidence of tachyarrhythmic rhythms, which include ventricular fibrillation (VF) and pulseless ventricular tachycardia (VT), has been noted to be progressively decreasing in multiple studies of OHCA. Improved medical and surgical therapies for ischemic heart disease, and the widespread use of implantable cardiac defibrillators (ICDs), have likely contributed to a declining incidence of VF arrest and may result in conversion of an otherwise VF event into a pulseless electrical activity (PEA) arrest. As the incidence of VF has declined, it is unclear if the absolute incidence of non-tachyarrhythmic rhythms has increased or remained largely unchanged. This article discusses the changing rates of presenting rhythms in sudden cardiac arrest, the underlying cellular mechanisms of PEA, the factors contributing to the relative increase in the rate of PEA arrests, and current treatment options. |
10,721 | Mitral valve repair for atrial functional mitral regurgitation in patients with chronic atrial fibrillation. | Atrial functional mitral regurgitation (MR) has been recently described in patients with chronic atrial fibrillation (AF). However, the results of surgical mitral valve (MV) repair for this type of MR have not been comprehensively reported. Our study aimed to address this deficiency.</AbstractText>We retrospectively studied 10 chronic AF patients who underwent MV repair for atrial functional MR with normal left ventricular dimension and preserved left ventricular systolic function. All patients had chronic heart failure (HF) symptoms and at least one prior admission for HF complicated by severe MR.</AbstractText>Ring annuloplasty was performed in all patients; the median ring size was 26 mm (range, 26-30 mm). Concomitant tricuspid valve repair was undertaken in all patients. Preoperatively, left atrial (LA) diameter on the parasternal long-axis view, LA volume index and mitral annular diameter were 52 ± 9 mm, 72 ± 26 ml/m(2) and 33 ± 4 mm, respectively. There was no mortality and no re-admission due to HF during follow-up (range, 10-52 months). MR at the most recent examination was mild or improved in degree in all patients. The LA volume index decreased from the preoperative period, measuring 48 ± 17 ml/m(2) at the most recent period (P = 0.03). The New York Heart Association functional class dramatically improved from the preoperative period to the most recent period (from 3.0 ± 0.7 to 1.2 ± 0.4, P < 0.0001).</AbstractText>Our results suggest that MV repair leads to reductions in MR, LA size and HF symptoms, and that it may prevent future HF events in patients with atrial functional MR.</AbstractText>© The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.</CopyrightInformation> |
10,722 | Antiarrhythmic Effect of Either Negative Modulation or Blockade of Small Conductance Ca2+-activated K+ Channels on Ventricular Fibrillation in Guinea Pig Langendorff-perfused Heart. | During recent years, small conductance Ca-activated K (SK) channels have been reported to play a role in cardiac electrophysiology. SK channels seem to be expressed in atria and ventricles, but from a functional perspective, atrial activity is predominant. A general notion seems to be that cardiac SK channels are predominantly coming into play during arrhythmogenic events where intracellular concentration of Ca is increased. During ventricular fibrillation (VF), a surge of [Ca]i has the potential to bind to and open SK channels. To obtain mechanistic insight into possible roles of SK channels during VF, we conducted experiments with an SK channel pore blocker (ICA) and a negatively allosteric modulator (NS8395) in a Langendorff-perfused heart model. Both compounds increased the action potential duration, effective refractory period, and Wenckebach cycle length to comparable extents. Despite these similarities, the SK channel modulator was found to revert and prevent VF more efficiently than the SK channel pore blocker. In conclusion, either negative allosteric modulation of the SK channel with NS8593 is more favorable than pure channel block with ICA or the 2 compounds have different selectivity profiles that makes NS8593 more antiarrhythmic than ICA in a setting of VF. |
10,723 | Velocity quantification by electrocardiography-gated phase contrast magnetic resonance imaging in patients with cardiac arrhythmia: a simulation study based on real time transesophageal echocardiography data in atrial fibrillation. | To systematically investigate the impact of beat-to-beat variations on electrocardiography (ECG)-gated multibeat flow imaging with phase contrast (PC) magnetic resonance imaging (MRI) based on real time in vivo transesophageal echocardiography (TEE) data in patients with known arrhythmia.</AbstractText>Real-time 2-dimensional Doppler TEE was performed in five patients with atrial fibrillation (4 men, age = 64 ± 8.7 years). The TEE data provided real-time left atrial (LA) and left ventricular (LV) flow velocities in consecutive cardiac cycles with different RR interval durations. The PC MRI acquisitions were simulated from the TEE velocity measures by constructing time-resolved k-space data for segmented sampling schemes typically used for ECG-gated 2-dimensional PC MRI. Each simulation was repeated 100 times to minimize effects from data that may be weighted to a particular beat in the center of k-space. The resulting LA and LV velocities were compared to the average TEE velocities and data from individual cardiac cycles.</AbstractText>Despite beat-to-beat variations of velocities in TEE data, ECG-gated flow imaging with MRI could reproduce persistent average LA and LV mean velocities within 7.0% to 7.4% compared to TEE.</AbstractText>The PC MRI velocity measurements in patients with varying RR interval durations are not significantly different from time-averaged real-time velocity data for a typical segmented k-space data acquisition schemes. Though beat-to-beat variations in atrial velocities that were observed with TEE cannot be detected with ECG-gated multibeat PC MRI, it can reliably assess average flow patterns across multiple beats.</AbstractText> |
10,724 | Preoperative Echocardiographic Parameters of Diastolic Dysfunction Did Not Provide a Predictive Value for Postoperative Atrial Fibrillation in Lung and Esophageal Cancer Surgery. | To evaluate the predictive value of preoperative transthoracic echocardiography in the development of postoperative atrial fibrillation after non-cardiac thoracic surgery.</AbstractText>This was a retrospective study.</AbstractText>Academic hospital.</AbstractText>A total of 703 adult patients with non-small cell lung cancer.</AbstractText>None.</AbstractText>Retrospective data of 177 non-cardiac thoracic surgical oncologic patients undergoing lung or esophageal cancer surgery with preoperative transthoracic echocardiograms (TTE) (within 30 days before surgery) were analyzed. The Wilcoxon rank sum test was used to evaluate the difference in continuous variables. Fisher's exact test or the chi-square test was used to evaluate the association between two categoric variables. Logistic regression models were used for multivariate analysis to include important and significant covariates. Among the demographic and echocardiographic variables measured age, systemic hypertension, e` septal, e` lateral and E/e` ratio were significantly different between patients who would develop postoperative atrial fibrillation (POAF) and those who did not. The logistic regression models only identify age as a predictor factor of POAF.</AbstractText>These results were similar to those published elsewhere on POAF incidence and risk factors. The preoperative echocardiographic variables in this study did not provide predictive value for POAF in non-cardiac thoracic surgery.</AbstractText>Copyright © 2015 Elsevier Inc. All rights reserved.</CopyrightInformation> |
10,725 | Amplitude-spectral area and chest compression release velocity independently predict hospital discharge and good neurological outcome in ventricular fibrillation out-of-hospital cardiac arrest. | In out-of-hospital cardiac arrest (OHCA) with ventricular fibrillation (VF) the frequency-based waveform characteristic, amplitude-spectral area (AMSA) is associated with hospital discharge and good neurological outcome, yet AMSA is also known to increase in response to chest compressions (CC). In addition to rate and depth, well performed CC provides good chest recoil without leaning, reflected in the release velocity (RV). We hypothesized that AMSA is associated with hospital discharge and good neurological outcome independent of CC quality.</AbstractText>OHCA patients (age ≥ 18), with initial rhythm of VF from an Utstein-Style database were analyzed. AMSA was measured prior to each shock, and averaged for each subject (AMSA-avg). Primary endpoint was hospital discharge and secondary endpoint was a good neurological outcome. Univariate and stepwise multivariable logistic regression, and receiver-operator-characteristic (ROC) analyses were performed. Factors analyzed were age, sex, witnessed status, time from dispatch to monitor/defibrillator application, number of shocks, first shock AMSA (AMSA1), AMSA-avg, averaged pre-shock pause, CC rate, depth, and RV.</AbstractText>140 subjects were analyzed. Hospital discharge was 31% and with good neurological outcome in 24% (77% of those discharged). AMSA-avg (p < 0.001), RV (p = 0.002), and age (p = 0.029) were independently associated with hospital discharge, with a non-significant trend for witnessed status (p = 0.069), with AUC = 0.846 for the multivariate model. For good neurological outcome, AMSA-avg (p = 0.001) and RV (p = 0.001) remained independently significant, with AUC = 0.782.</AbstractText>In OHCA with an initial rhythm of VF, AMSA-avg and CC RV are both highly and independently associated with hospital discharge and good neurological outcome.</AbstractText>Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
10,726 | Functional (ischemic) mitral regurgitation in acute phase of myocardial infarction: Associated clinical factors and in-hospital outcomes. | Mitral regurgitation (MR) after myocardial infarction (MI) carries adverse prognosis. The objective of this study was to assess the impact of functional MR on adverse in-hospital outcomes in acute MI.</AbstractText>A total of 569 patients with first ever acute MI were divided into three groups: no MR, mild MR (regurgitant orifice area <0.2 cm(2)) and moderate-severe MR group (regurgitant orifice area more or equal >0.2 cm(2)). Clinical profile and in-hospital outcomes were compared among the groups.</AbstractText>Patients with increasing grade of MR were elder (P<0.001), more likely to be female (P=0.003), have atrial fibrillation (P<0.001), higher peak C-reactive protein values (P=0.001), multivessel coronary artery disease (P<0.001), and less likely to have dyslipidemia (P=0.029). Ejection fraction, age, atrial fibrillation and left ventricular end diastolic diameter index were independent predictors of moderate and severe MR (P<0.001). In hospital cardiac death and decompensated heart failure was more prevalent in moderate-severe MR group.</AbstractText>Moderate and severe MR in acute MI is related to age, atrial fibrillation, increased left ventricular diastolic dimensions and decreased ejection fraction. Moderate and severe, but not mild MR is an important clinical contributor to in-hospital cardiac death.</AbstractText>Copyright © 2015 Lithuanian University of Health Sciences. Production and hosting by Elsevier Urban & Partner Sp. z o.o. All rights reserved.</CopyrightInformation> |
10,727 | Meta-analysis of the usefulness of Mitraclip in patients with functional mitral regurgitation. | Midterm outcomes for patients presenting with heart failure and functional mitral regurgitation (MR) treated with Mitraclip remain unclear. Pubmed, Medline, and Google Scholar were systematically searched for studies enrolling patients with severe-moderate MR who underwent Mitraclip implantation. All events after at least 6 months were the primary safety end point (including death, rehospitalization for heart failure, and reinterventions), whereas change in the ejection fraction, left ventricular volumes, arterial pulmonary pressure, and left atrial diameters were considered as secondary end points. Meta-regression analysis was performed to evaluate the effect of baseline clinical and echocardiographic parameters on efficacy outcomes: 875 patients were included in 9 studies; 1.48 clips (1.3 to 1.7) for patients were implanted, and after a median follow-up of 9 months (6 to 12), 409 patients (78% [75% to 83%]) were in class New York Heart Association I/II and 57 (11% [8% to 14%]) still had moderate-to-severe MR. Overall adverse events occurred in 137 (26% [20% to 31%]) of the patients and 78 (15% [1% to 17%]) of them died; 6-minute walk test improved by 100 m (83 to 111), whereas a significant reduction in left ventricular volumes and systolic pulmonary pressure was reported. At meta-regression analysis, an increase in left ventricle systolic volumes positively affected reduction of volumes after Mitraclip, whereas atrial fibrillation reduced the positive effect of the valve implantation on ejection fraction on end-diastolic and -systolic volumes. In conclusion, Mitraclip represents an efficacious strategy for patients with heart failure and severe MR. It offers a significant improvement in functional class and in cardiac remodeling, in patients with severely dilated hearts as well, although its efficacy remains limited in the presence of atrial fibrillation. |
10,728 | Genotype-dependent differences in age of manifestation and arrhythmia complications in short QT syndrome. | Short QT syndrome (SQTS) is a rare inheritable arrhythmia, associated with atrial and ventricular fibrillations, caused by mutations in six cardiac ion channel genes with high penetrance. However, genotype-specific clinical differences between SQTS patients remain to be elucidated.</AbstractText>We screened five unrelated Japanese SQTS families, and identified three mutations in KCNH2 and KCNQ1. A novel mutation KCNH2-I560T, when expressed in COS-7 cells, showed a 2.5-fold increase in peak current density, and a positive shift (+14 mV) of the inactivation curve compared with wild type. Computer simulations recapitulated the action potential shortening and created an arrhythmogenic substrate for ventricular fibrillation. In another family carrying the mutation KCNQ1-V141M, affected members showed earlier onset of manifestation and frequent complications of bradyarrhythmia. To determine genotype-specific phenotypes in SQT1 (KCNH2), SQT2 (KCNQ1), and other subtypes SQT3-6, we analyzed clinical variables in 65 mutation-positive patients among all the 132 SQTS cases previously reported. The age of manifestation was significantly later in SQT1 (SQT1: 35 ± 19 years, n = 30; SQT2: 17 ± 25 years, n = 8, SQT3-6: 19 ± 15 years, n = 15; p = 0.011). SQT2 exhibited a higher prevalence of bradyarrhythmia (SQT2: 6/8, 75%; non-SQT2: 5/57, 9%; p < 0.001) and atrial fibrillation (SQT2: 5/8, 63%; non-SQT2: 12/57, 21%; p = 0.012). Of 51 mutation-positive individuals from 16 SQTS families, nine did not manifest short QT, but exhibited other ECG abnormalities such as atrial fibrillation. The resulting penetrance, 82%, was lower than previously recognized.</AbstractText>We propose that SQTS patients may exhibit different clinical manifestations depending upon their genotype.</AbstractText>Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
10,729 | Management of ventricular arrhythmias in structural heart disease. | Ventricular arrhythmias (VA) are a source of significant morbidity and mortality in patients with structural heart disease (SHD). The advent of the implantable cardiac defibrillator (ICD) has had a positive effect on mortality, but the associated morbidity remains a significant problem. Modern treatment of VA has advanced far beyond medical therapy and includes strategies as simple as intelligent ICD programming and as complex as catheter ablation (CA). In these pages, the spectrum of management strategies will be discussed; from anti-arrhythmic drugs and ICD implantation and programming to CA and autonomic modulation. The focus of this review will be on strategies for secondary prevention of VA in patients with SHD, supported by clinical evidence for their utilization. |
10,730 | Spatially Discordant Alternans and Arrhythmias in Tachypacing-Induced Cardiac Myopathy in Transgenic LQT1 Rabbits: The Importance of IKs and Ca2+ Cycling. | Remodeling of cardiac repolarizing currents, such as the downregulation of slowly activating K+ channels (IKs), could underlie ventricular fibrillation (VF) in heart failure (HF). We evaluated the role of Iks remodeling in VF susceptibility using a tachypacing HF model of transgenic rabbits with Long QT Type 1 (LQT1) syndrome.</AbstractText>LQT1 and littermate control (LMC) rabbits underwent three weeks of tachypacing to induce cardiac myopathy (TICM). In vivo telemetry demonstrated steepening of the QT/RR slope in LQT1 with TICM (LQT1-TICM; pre: 0.26±0.04, post: 0.52±0.01, P<0.05). In vivo electrophysiology showed that LQT1-TICM had higher incidence of VF than LMC-TICM (6 of 11 vs. 3 of 11, respectively). Optical mapping revealed larger APD dispersion (16±4 vs. 38±6 ms, p<0.05) and steep APD restitution in LQT1-TICM compared to LQT1-sham (0.53±0.12 vs. 1.17±0.13, p<0.05). LQT1-TICM developed spatially discordant alternans (DA), which caused conduction block and higher-frequency VF (15±1 Hz in LQT1-TICM vs. 13±1 Hz in LMC-TICM, p<0.05). Ca2+ DA was highly dynamic and preceded voltage DA in LQT1-TICM. Ryanodine abolished DA in 5 out of 8 LQT1-TICM rabbits, demonstrating the importance of Ca2+ in complex DA formation. Computer simulations suggested that HF remodeling caused Ca2+-driven alternans, which was further potentiated in LQT1-TICM due to the lack of IKs.</AbstractText>Compared with LMC-TICM, LQT1-TICM rabbits exhibit steepened APD restitution and complex DA modulated by Ca2+. Our results strongly support the contention that the downregulation of IKs in HF increases Ca2+ dependent alternans and thereby the risk of VF.</AbstractText> |
10,731 | Double Sequential Defibrillation for Refractory Ventricular Fibrillation: A Case Report. | A 40-year-old male struck his chest against a pole during a basketball game and had sudden out-of-hospital cardiac arrest. After bystander cardiopulmonary resuscitation, fire and emergency medical services personnel provided six defibrillation attempts prior to emergency department arrival. A 7th attempt in the emergency department using a different vector was unsuccessful. On the 8th attempt, using a second defibrillator with defibrillator pads placed adjacent to the primary set of defibrillator pads, two shocks were administered in near simultaneous fashion. The double sequential defibrillation was successful and the patient had return of spontaneous circulation at the next pulse check. He recovered in the intensive care unit, was discharged home 1 month later, and continues to follow up in clinic over 1 year later with a Cerebral Performance Category score of 1 (short-term memory deficits). |
10,732 | The relationship between repolarization parameters and serum electrolyte levels in patients with J wave syndromes. | Intravenous administration of magnesium (Mg(2+)) is effective for polymorphic ventricular tachycardia via homogenization of transmural ventricular repolarization. Mg(2+) likely plays some role in the heterogeneity of repolarization in J wave syndromes.</AbstractText>To investigate the relationship between the repolarization parameters and serum Mg(2+), potassium (K(+)), and calcium (Ca(2+)) levels in J wave syndromes.</AbstractText>Thirteen J-wave syndrome patients (Brugada and early repolarization [ER] syndromes), with documented episodes of ventricular fibrillation (VF), and 13 ER pattern (ERP) or Brugada type ECG patients were enrolled (25 males, mean age 48 ± 15 years). The 12-lead ECG-derived parameters including the QT, QT dispersion (QTd), Tpeak-Tend (Tp-e) interval, Tp-e dispersion (Tp-ed), Tp-e/QT ratio, and activation recovery interval (ARI) dispersion were calculated; the correlations between these parameters and electrolytes including Mg(2+), K(+), and Ca(2+) were analyzed.</AbstractText>Although there was no association between serum K(+) or Ca(2+) and QTd, there was a strong negative correlation between serum Mg(2+) and QTd in J wave syndrome patients with a history of VF (r = -0.715, p = 0.006). Also, there was a tendency for a negative correlation between Mg(2+) and Tp-ed or ARI dispersion in J wave syndrome patients with a history of VF (r = -0.513, p = 0.072 and r = -0.53, p = 0.063, respectively). On the other hand, in 13 patients with a Brugada type ECG or ERP, no correlation was observed between serum Mg(2+) and the QTd, Tp-ed or ARI dispersion.</AbstractText>Serum Mg(2+) may play an important role in the cardiac repolarization process in J wave syndromes.</AbstractText> |
10,733 | Incidence and Predictors of New-Onset Atrial Fibrillation in Septic Shock Patients in a Medical ICU: Data from 7-Day Holter ECG Monitoring. | We investigated incidence, risk factors for new-onset atrial fibrillation (NAF), and prognostic impact during septic shock in medical Intensive Care Unit (ICU) patients.</AbstractText>Prospective, observational study in a university hospital. Consecutive patients from 03/2011 to 05/2013 with septic shock were eligible. Exclusion criteria were age <18 years, history of AF, transfer with prior septic shock. Included patients were equipped with long-duration (7 days) Holter ECG monitoring. NAF was defined as an AF episode lasting >30 seconds. Patient characteristics, infection criteria, cardiovascular parameters, severity of illness, support therapies were recorded.</AbstractText>Among 66 patients, 29(44%) developed NAF; 10 (34%) would not have been diagnosed without Holter ECG monitoring. NAF patients were older, with more markers of heart failure (troponin and NT-pro-BNP), lower left ventricular ejection fraction (LVEF), longer QRS duration and more nonsustained supra ventricular arrhythmias (<30s) on day 1 than patients who maintained sinus rhythm. By multivariate analysis, age (OR: 1.06; p = 0.01) and LVEF<45% (OR: 13.01, p = 0.03) were associated with NAF. NAF did not predict 28 or 90 day mortality.</AbstractText>NAF is common, especially in older patients, and is associated with low ejection fraction. We did not find NAF to be independently associated with higher mortality.</AbstractText> |
10,734 | Predictors of long-term outcomes in patients with hypertrophic cardiomyopathy undergoing cardiopulmonary stress testing and echocardiography. | Patients with hypertrophic cardiomyopathy (HCM) have exercise intolerance due to left ventricular outflow tract (LVOT) obstruction, mitral regurgitation, and left ventricular dysfunction. We sought to study predictors of outcomes in HCM patients undergoing cardiopulmonary stress testing (CPT).</AbstractText>We studied 1,005 HCM patients (50 ± 14 years, 64% men, 77% on β-blockers) who underwent CPT with echocardiography. Clinical, echocardiographic, and exercise variables (peak oxygen consumption [VO2] and heart rate recovery [HRR] at first minute postexercise) were recorded. End point was a composite of death, appropriate defibrillator discharges, resuscitated sudden death, stroke, and heart failure admission.</AbstractText>Mean left ventricular ejection fraction (LVEF), postexercise LVOT gradient, and peak VO2 were 62% ± 6%, 92 ± 51 mm Hg, and 21 ± 6 mL kg(-1) min(-1), respectively. Despite 789 patients (78%) being in New York Heart Association classes I to II, only 8% achieved >100% age-gender predicted peak VO2, whereas 77% and 15% achieved 50% to 100% and <50%, respectively. Left ventricular outflow tract gradient ≥30 mm Hg was observed in 83% patients, whereas 23% had abnormal HRR. More than 5.5 ± 4 years, there were 94 (9%) events; 511 (50%) patients underwent surgery for LVOT obstruction. Multivariable Cox proportional analysis demonstrated % age-gender predicted peak VO2 (hazard ratio [HR] 0.96 [0.93-0.98]), normal vs abnormal HRR (HR 0.48 [0.32-0.73]), higher LVEF (HR 0.96 [0.93-0.98]), surgery (0.53 [0.33-0.83]), and atrial fibrillation (HR 1.65 [1.04-2.60]) were associated with outcomes (all P < .05).</AbstractText>In HCM patients undergoing CPT, a higher % of achieved age-gender predicted VO2 and surgical relief of LVOT obstruction were associated with better outcomes, whereas abnormal HRR, atrial fibrillation, and lower LVEF were associated with worse outcomes.</AbstractText>Copyright © 2015 Elsevier Inc. All rights reserved.</CopyrightInformation> |
10,735 | Impact of weight reduction on pericardial adipose tissue and cardiac structure in patients with atrial fibrillation. | Obesity and pericardial adipose tissue are independent risk factors for atrial fibrillation (AF) and adverse cardiac structural remodeling. The effect of weight reduction on pericardial adipose tissue and cardiac structure remains unknown.</AbstractText>We prospectively performed cardiac magnetic resonance imaging on 87 participants with AF undergoing either structured weight management (intervention) or general lifestyle advice (control). We measured pericardial adipose tissue, atrial and ventricular volumes, and myocardial mass at baseline and 12 months.</AbstractText>In total, 69 participants underwent baseline and 12-month follow-up cardiac magnetic resonance imaging (intervention n = 36 and controls n = 33). From baseline to 12 months, weight loss (kg, mean [95% CI]) was greater in the intervention group from 101.5 kg (97.2-105.8 kg) to 86.5 kg (81.2-91.9 kg) as compared with controls from 102.6 kg (97.2-108.1 kg) to 98.7 kg (91.0-106.3 kg) (time-group interaction P < .001). The intervention group showed a reduction in left atrial volumes (mL) from 105.0 mL (98.9-111.1 mL) to 96.4 mL (91.6-101.1 mL), whereas the change in the control group was from 108.8 mL (99.6-117.9 mL) to 108.9 mL (99.8-118.0 mL) (time-group interaction P < .001). There was a decline in pericardial adipose tissue (cm(3)) from 140.9 cm(3) (129.3-152.4 cm(3)) to 118.8 cm(3) (108.1-129.6 cm(3)) and myocardial mass (g) from 137.6 g (128.1-147.2 g) to 123.1 g (114.5-131.7 g) in the intervention group, whereas the change in the control group was from 143.2 cm(3) (124.6-161.7 cm(3)) to 147.2 cm(3) (128.9-165.4 cm(3)) for pericardial adipose tissue and 138.3 g (124.8-151.8 g) to 140.7 g (127.4-154.1 g) for myocardial mass (both variables, time-group interaction P < .001).</AbstractText>Weight reduction results in favorable structural remodeling and a reduction in pericardial adipose tissue burden.</AbstractText>Copyright © 2015 Elsevier Inc. All rights reserved.</CopyrightInformation> |
10,736 | Epicardial phrenic nerve displacement during catheter ablation of atrial and ventricular arrhythmias: procedural experience and outcomes. | Arrhythmia origin in close proximity to the phrenic nerve (PN) can hinder successful catheter ablation. We describe our approach with epicardial PN displacement in such instances.</AbstractText>PN displacement via percutaneous pericardial access was attempted in 13 patients (age 49±16 years, 9 females) with either atrial tachycardia (6 patients) or atrial fibrillation triggered from a superior vena cava focus (1 patient) adjacent to the right PN or epicardial ventricular tachycardia origin adjacent to the left PN (6 patients). An epicardially placed steerable sheath/4 mm-catheter combination (5 patients) or a vascular or an esophageal balloon (8 patients) was ultimately successful. Balloon placement was often difficult requiring manipulation via a steerable sheath. In 2 ventricular tachycardia cases, absence of PN capture was achieved only once the balloon was directly over the ablation catheter. In 3 atrial tachycardia patients, PN displacement was not possible with a balloon; however, a steerable sheath/catheter combination was ultimately successful. PN displacement allowed acute abolishment of all targeted arrhythmias. No PN injury occurred acutely or in follow up. Two patients developed acute complications (pleuro-pericardial fistula 1 and pericardial bleeding 1). Survival free of target arrhythmia was achieved in all atrial tachycardia patients; however, a nontargeted ventricular tachycardia recurred in 1 patient at a median of 13 months' follow up.</AbstractText>Arrhythmias originating in close proximity to the PN can be targeted successfully with PN displacement with an epicardially placed steerable sheath/catheter combination, or balloon, but this strategy can be difficult to implement. Better tools for phrenic nerve protection are desirable.</AbstractText>© 2015 American Heart Association, Inc.</CopyrightInformation> |
10,737 | Sudden cardiac death in CKD patients. | The risk of sudden cardiac death (SCD) is high in chronic kidney disease patients, and it increases with the progression of kidney function deterioration. The most common causes of SDC are the following: ventricular tachycardia, ventricular tachyarrhythmia, tachycardia torsade de pointes, sustained ventricular fibrillation and bradyarrhythmia. Dialysis influences cardiovascular system and results in hemodynamic disturbances as well as electrolyte shifts altering myocardial electrophysiology. Studies suggest that this procedure exerts both detrimental (poor volume control can exacerbate hypertension and left ventricle hypertrophy) and beneficial effects (associated with fluid removal and subsequent decrease in left ventricle stretch). Dialysis-related vulnerability to serious arrhythmias is the result of sudden shifts in fluid status and electrolytes, particularly potassium, which alter the physiological milieu. Also Ca(2+) ions, in which concentration alters during dialysis, are of key importance in the contraction of vascular smooth muscle cells and cardiac myocytes, thus exerting significant effects on hemodynamics. Due to the fact that SCD occurs with similar frequency in peritoneal dialysis and in hemodialysis patients, it seems that end-stage renal disease factors are more important than the specific ones associated with dialysis type. The results of randomized trials suggested that hemodialysis patients may not derive the same benefit of cardiovascular disease therapy including beta-blockers, calcium channel blockers and angiotensin-converting enzyme inhibitors as the general population with normal kidney function. Noninvasive tests used to stratify SCD risk in HD patients have poor positive value, and thus, combining tests including HRV, baroreceptor sensitivity and effectiveness index as well as its function indices and heart rate turbulence should be implemented. There are only few large randomized placebo-controlled trials assessing the influence of cardioprotective medications or implantable cardioverter defibrillator (ICD) implantation in dialysis patients on life quality and survival, and their results are sometimes contradictory. The decision concerning treatment and/or ICD implantation in this group of patients should be made on the basis of careful assessment of individual risk factors. Moreover, due to the high hazard of cardiovascular mortality including SCD in dialysis patients, physicians should concentrate on the early selection of high-risk patients, monitoring them and introduction of preventive measures. |
10,738 | The unexpected pitter patter: new-onset atrial fibrillation in pregnancy. | Background. Atrial fibrillation is a relatively uncommon but dangerous complication of pregnancy. Emergency physicians must know how to treat both stable and unstable tachycardias in late pregnancy. In this case, a 40-year-old female with a cerclage due to incompetent cervix and previous preterm deliveries presents in new-onset atrial fibrillation. Case Report. A previously healthy 40-year-old African American G2 P1 female with a 23-week twin gestation complicated by an incompetent cervix requiring a cervical cerclage presented to the emergency department with intermittent palpitations and shortness of breath for the past two months. EMS noted the patient to have a tachydysrhythmia, atrial fibrillation with rapid ventricular response. She was placed on a diltiazem drip, which was titrated to 15 mg/hr without successful rate control. Her heart rate remained in the 130s and the rhythm continued to be atrial fibrillation with RVR. Digoxin was then added as a second agent, and discussions about the potential risks of cardioversion in pregnancy ensued. Fortunately, the patient converted to sinus rhythm before cardioversion became necessary. The digoxin was discontinued; the diltiazem was also discontinued after the patient subsequently developed hypotension. "Why Should Emergency Physicians Be Aware of This?" New-onset atrial fibrillation is rare in pregnancy but can increase the mortality and morbidity of the mother and fetus if not treated promptly. |
10,739 | Obesity and atrial fibrillation: A comprehensive review of the pathophysiological mechanisms and links. | Obesity is a worldwide health problem with epidemic proportions that has been associated with atrial fibrillation (AF). Even though the underlying pathophysiological mechanisms have not been completely elucidated, several experimental and clinical studies implicate obesity in the initiation and perpetuation of AF. Of note, hypertension, diabetes mellitus, metabolic syndrome, coronary artery disease, and obstructive sleep apnea, represent clinical correlates between obesity and AF. In addition, ventricular adaptation, diastolic dysfunction, and epicardial adipose tissue appear to be implicated in atrial electrical and structural remodeling, thereby promoting the arrhythmia in obese subjects. The present article provides a concise overview of the association between obesity and AF, and highlights the underlying pathophysiological mechanisms. |
10,740 | Characteristics of Left Atrial Deformation Parameters and Their Prognostic Impact in Patients with Pathological Left Ventricular Hypertrophy: Analysis by Speckle Tracking Echocardiography. | The pathological process of left ventricular (LV) hypertrophy is associated with left atrial (LA) remodeling. This study was aimed to evaluate the prognostic value of LA strain parameters in patients with pathological LV hypertrophy.</AbstractText>This study included 95 patients with hypertensive heart disease (HHD: n = 24), hypertrophic cardiomyopathy (HCM: n = 56), cardiac amyloidosis (CA: n = 15), and control subjects (n = 20). We used two-dimensional speckle tracking echocardiography (STE) to analyze LA global strain. LA electromechanical conduction time (EMT) at the septal (EMT-septal) and lateral wall (EMT-lateral), and their time difference (EMT-diff) were calculated. The incidence of cardiac death and heart failure hospitalization was defined as major cardiac events and that of atrial fibrillation as secondary outcome.</AbstractText>Left atrial volume index was increased and LA booster strain was decreased in the HCM and CA groups compared with the HHD group. EMT-lateral was increased in the diseased groups compared with the control. EMT-diff was prolonged in the CA group compared with the HCM group. During the follow-up period (mean 3.4 years), major cardiac events and atrial fibrillation occurred in 17 and 13 patients, respectively. The occurrence of atrial fibrillation was associated with CA etiology, E/e', LA volume index, LAa, and EMT-lateral. The incidence of major cardiac events was independently correlated with LA volume index and EMT-diff in multivariate analysis.</AbstractText>This study suggested that the EMT-diff could discriminate patients with a high risk of cardiac events among patients with pathological LV hypertrophy.</AbstractText>© 2015, Wiley Periodicals, Inc.</CopyrightInformation> |
10,741 | Balancing the Risk of Bleeding and Stroke in Patients With Atrial Fibrillation After Percutaneous Coronary Intervention (from the AVIATOR Registry). | Patients with atrial fibrillation (AF) who underwent percutaneous coronary intervention (PCI) are at elevated risk for bleeding and thromboembolic ischemic events. Currently, guidelines on antithrombotic treatment for these patients are based on weak consensus. We describe patterns and determinants of antithrombotic prescriptions in this population. The Antithrombotic Strategy Variability in Atrial Fibrillation and Obstructive Coronary Disease Revascularized with PCI Registry was an international observational study of 859 consecutive patients with AF who underwent PCI from 2009 to 2011. Patients were stratified by treatment at discharge with either dual antiplatelet therapy (DAPT; aspirin plus clopidogrel) or triple therapy (TT; warfarin plus DAPT). Bleeding and thromboembolism risks were assessed by the HAS-BLED and CHADS2 scores, respectively, and predictors of TT prescription at discharge were identified. Major adverse cardiovascular events and clinically relevant bleeding (Bleeding Academic Research Consortium score ≥2) at 1-year follow-up were compared across antithrombotic regimens. Compared with patients on DAPT (n = 488; 57%), those given TT (n = 371; 43%) were older, with higher CHADS2 scores, lower left ventricular ejection fraction, and more often had permanent AF, single-vessel coronary artery disease, and bare-metal stents. In multivariate analysis, increasing thromboembolic risk (CHADS2) was associated with a higher rate of TT prescription at discharge (intermediate vs low CHADS2: odds ratio 2.2, 95% confidence interval [CI] 2.0 to 3.3, p <0.01; high vs low CHADS2: odds ratio 1.6, 95% CI 2.6 to 4.3, p <0.01 for TT). However, there was no significant association between bleeding risk and TT prescription in the overall cohort or within each CHADS2 risk stratum. The rates of major adverse cardiovascular events were similar for patients discharged on TT or DAPT (20% vs 17%, adjusted hazard ratio 0.8, 95% CI 0.5 to 1.1, p = 0.19), whereas the rate of Bleeding Academic Research Consortium ≥2 bleeding was higher in patients discharged on TT (11.5% vs 6.4%, adjusted hazard ratio 1.8, 95% CI 1.1 to 2.9, p = 0.02). In conclusion, the choice of the intensity of antithrombotic therapy correlated more closely with the risk of ischemic rather than bleeding events in this cohort of patients with AF who underwent PCI. |
10,742 | Simultaneous fat and bone assessment in hospitalized heart failure patients using non-contrast-enhanced computed tomography. | Heart failure (HF) is associated with adverse metabolic influences and provokes fat loss as well as bone and muscle loss at the terminal stages. Pericardial fat is an ectopic fat depot that can potentially affect the myocardium, but the role of pericardial fat in HF is unclear. We sought to characterize pericardial fat in HF, particularly in association with bone tissue using cardiac computed tomography (CT).</AbstractText>In 61 consecutive hospitalized HF patients with left ventricular ejection fraction ≤50%, pericardial fat volume (PFV), CT density in the thoracic vertebrae, and ectopic calcification in the aortic valve were assessed simultaneously using electrocardiogram-gated non-contrast-enhanced CT.</AbstractText>The mean PFV was 93.5±50.6cm(3), which might reflect the total body fat measured with dual energy X-ray absorptiometry (Pearson's r=0.48, p=0.01). The PFV index, defined as the PFV/body surface area, was significantly higher among older patients (>65 years; 63.5±30.6cm(3)/m(2) vs. 42.7±17.1cm(3)/m(2), p<0.01) and among patients with atrial fibrillation (AF; 70.9±36.4cm(3)/m(2) vs. 48.8±21.2cm(3)/m(2), p<0.01) and hypertension (60.7±29.3cm(3)/m(2) vs. 41.5±18.2cm(3)/m(2), p<0.01) compared to patients without these conditions. The PFV indices were comparable between the patients with and without ischemic etiology, diabetes, and renal dysfunction. Patients with increased PFV indices (above the median) exhibited lower CT density in the thoracic vertebrae (134±41 Hounsfield units vs. 161±57 Hounsfield units, p=0.04), and were more likely to have aortic valve calcification (48% vs. 18%, p=0.02) and N-telopeptide (bone resorption marker; 20.7±5.2nmolBCE/mmolCr vs. 25.5±5.9nmolBCE/mmolCr, p=0.03) levels than those without increased PFV indices.</AbstractText>We simultaneously assessed the pericardial fat and bone tissue of HF patients with CT and successfully characterized AF, hypertension, and advanced age as factors that are associated with increased PFV. PFV was correlated with bone tissues and alterations in bone turnover.</AbstractText>Copyright © 2015 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.</CopyrightInformation> |
10,743 | Cardiac sodium channel blockade after an intentional ingestion of lacosamide, cyclobenzaprine, and levetiracetam: Case report. | Lacosamide treats partial seizures by enhancing slow inactivation of voltage-gated sodium channels. The described cardiac toxicity of lacosamide in the literature to date includes atrioventricular blockade (PR prolongation), atrial flutter, atrial fibrillation, sinus pauses, ventricular tachycardia and a single cardiac arrest. We report a second case of cardiac arrest following an intentional lacosamide overdose.</AbstractText>A 16 year-old female with a seizure disorder was found unresponsive in pulseless ventricular tachycardia after intentionally ingesting 4.5 g (76 mg/kg) lacosamide, 120 mg (2 mg/kg) cyclobenzaprine and an unknown amount of levetiracetam. Exact time of ingestion was unknown. Her initial electrocardiogram (ECG) demonstrated sinus tachycardia at 139 beats per minute, QRS duration 112 ms, and terminal R-wave in lead aVR > 3 mm. Despite treatment with 150 mEq of sodium bicarbonate, she had persistent EKG findings eight hours after presentation. Her serum lacosamide concentration nine hours after presentation was elevated at 22.8 μg/mL, while serum cyclobenzaprine concentration was 16 ng/mL (therapeutic: 10-30 ng/mL), and serum levetiracetam concentration was 22.7 μg/mL (therapeutic: 12-46 μg/mL). On hospital day three, ECG demonstrated resolution of the terminal R-wave with QRS of 78 ms. The patient recovered without physical or neurologic sequelae.</AbstractText>The patient's lacosamide, cyclobenzaprine and levetiracetam overdose was associated with QRS prolongation and terminal right axis deviation--suggesting sodium channel blockade as a likely etiology for her cardiac arrest. Cyclobenzaprine has potential for sodium channel blockade and ventricular dysrhythmias although cardiac toxicity due to cyclobenzaprine alone is rare. The combination of cyclobenzaprine with lacosamide may have resulted in cardiovascular collapse. In conclusion, overdose of lacosamide combined with therapeutic concentrations of sodium channel blocking xenobiotics may cause cardiac conduction delays and cardiac arrest.</AbstractText> |
10,744 | Ellagic acid improved arrhythmias induced by CaCL2 in the rat stress model. | In ventricular arrhythmias, due to their free radical scavenging action, antioxidant agents are usually used in the treatment of cardiovascular disease. Since stress is considered as risk factor for increased mortality by causing malignant arrhythmias, the study was designed to evaluate the cardioprotective effects of ellagic acid (EA) on CaCl2-induced arrhythmias in rat stress model.</AbstractText>Male Sprague-Dawley rats (200-250 g) were divided into four groups: Group I: Control rats (2 ml of saline by gavage), Group II: Rats treated with EA (15 mg/kg, gavage), Group III: stress group, Group IV: received EA plus stress. Stress was applied in a restrainer box (6 hour/day, 21 days). After induction of anesthesia, lead II electrocardiogram was recorded for calculating heart rate and QRS complex. The arrhythmia was produced by injection of CaCl2 solution (140 mg/kg, iv) and incidences of Ventricular fibrillation, Ventricular premature beats and Ventricular tachycardia were recorded. Results were analyzed by using one-way ANOVA and Fisher`s exact test. p<0.05 was considered as significant level.</AbstractText>The results showed a positive inotropic effect and negative chronotropic effect for the EA group in comparison with the control group. Incidence rates (%) of premature beats, ventricular fibrillation and ventricular tachycardia in stress group and all the arrhythmia parameters decreased in groups which received EA.</AbstractText>By decreasing the incidence rates of premature beats, fibrillation and ventricular tachycardia in groups which received EA, ellagic acid probably acted as an anti-arrhythmic agent which showed to have aprotective functionin heart.</AbstractText> |
10,745 | Long-term outcomes after transcatheter aortic valve replacement in high-risk patients with severe aortic stenosis: the U.K. Transcatheter Aortic Valve Implantation Registry. | The U.K. Transcatheter Aortic Valve Implantation Registry reported 30-day and 1-year mortality rates of 7.1% and 21.4%, respectively, for patients who underwent transcatheter aortic valve replacement (TAVR) in the United Kingdom between 2007 and 2009. The study aim was to report long-term outcomes in this same cohort of patients.</AbstractText>There are few data on outcomes beyond 3 years after TAVR in any notable number of patients.</AbstractText>Data from all TAVR procedures performed in the United Kingdom between January 2007 and December 2009 were prospectively collected. All-cause mortality status was reported in March 2014. Mortality tracking was achieved in 97.7% patients.</AbstractText>The minimal time from replacement to census was 4.1 years, and the maximal time was 7.0 years. The 3- and 5-year survival rates were 61.2% and 45.5%, respectively. Independent predictors of 3-year mortality were renal dysfunction (hazard ratio [HR]: 1.65), atrial fibrillation (HR: 1.36), logistic European System for Cardiac Operative Risk Evaluation (EuroSCORE) ≥18.5 (HR: 1.33), respiratory dysfunction (HR: 1.28), and ventricular dysfunction (left ventricular ejection fraction <30%) (HR: 1.53). Coronary artery disease (HR: 1.28) and age (HR: 1.03) were additional independent predictors of mortality at 5 years. Stroke within 30 days of TAVR was the only independent procedural predictor of mortality at 3 and 5 years (HR: 2.17 at 3 years). Device type, access route, and paravalvular leak did not independently predict long-term outcome.</AbstractText>In the large U.K. Transcatheter Aortic Valve Implantation Registry, long-term outcomes after TAVR are favorable with 3- and 5-year survival rates of 61.2% and 45.5%, respectively. Long-term survival after TAVR is largely determined by intrinsic patient factors. Other than stroke, procedural variables, including paravalvular aortic leak, did not appear to be independent predictors of long-term survival.</AbstractText>Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
10,746 | Further evidence for the role of gap junctions in the delayed antiarrhythmic effect of cardiac pacing. | The objective of this study was to provide evidence that gap junctions are involved in the delayed antiarrhythmic effect of cardiac pacing. Twenty-four dogs were paced through the right ventricle (4 × 5 min, rate of 240 beats/min) 24 h prior to a 25 min occlusion of the left anterior descending coronary artery. Some of these paced dogs were infused with 50 (n = 7) or 100 μmol/L (n = 7) of the gap junction uncoupler carbenoxolone (CBX), prior to and during the occlusion. Ten sham-paced dogs, subjected only to occlusion, served as the controls. Cardiac pacing markedly reduced the number of ectopic beats and episodes of ventricular tachycardia (VT), as well the incidence of VT and ventricular fibrillation during occlusion. The changes in severity of ischaemia and tissue electrical resistance were also less marked compared with the unpaced controls. Pacing also preserved the permeability of gap junctions, the phosphorylation of connexin43, and the structural integrity of the intercalated discs. The closing of gap junctions with CBX prior to and during ischaemia markedly attenuated or even abolished these protective effects of pacing.</AbstractText>Our results support the previous findings that gap junctions play a role in the delayed antiarrhythmic effect of cardiac pacing.</AbstractText> |
10,747 | Ventricular rate during acute atrial fibrillation and outcome of electrical cardioversion: The FinCV Study. | The impact of ventricular rate (VR) on the outcome of electrical cardioversion (ECV) of acute atrial fibrillation (AF) is currently unknown. We aimed to determine the effect of VR during acute AF on the success of ECV, recurrence of AF, and occurrence of post-cardioversion complications in 30 days of follow-up.</AbstractText>A total of 6,624 ECVs were performed in 2,821 consecutive patients with AF lasting < 48 hours. VR ≤ 60 bpm was defined low, and VR ≥ 160 bpm high.</AbstractText>The median VR before ECV was 109 bpm. The success rate of ECV was 94.2%. Bradycardia occurred in 62 (0.9%) and thromboembolic complications in 39 (0.6%) ECVs. Low VR was observed before 75 (1.1%) ECVs, and male sex was its only independent predictor. High VR was observed in 165 (2.5%) ECVs. The independent predictors of high VR were younger age, < 12 h episode duration, no previous history of AF, and alcohol abuse. Low or high VR were not related to the success of ECV, incidence of thromboembolic or bradycardic complications, or recurrence of AF, although VR was significantly (P < 0.001) lower in the patients in whom AF recurred.</AbstractText>VR during acute AF does not affect the efficacy or safety of ECV.</AbstractText> |
10,748 | Prognostication of post-cardiac arrest coma: early clinical and electroencephalographic predictors of outcome. | To determine the temporal evolution, clinical correlates, and prognostic significance of electroencephalographic (EEG) patterns in post-cardiac arrest comatose patients treated with hypothermia.</AbstractText>Prospective cohort study of consecutive post-anoxic patients receiving hypothermia and continuous EEG monitoring between May 2011 and June 2014 (n = 100). In addition to clinical variables, 5-min EEG clips at 6, 12, 24, 48, and 72 h after return of spontaneous circulation (ROSC) were reviewed. EEG background was classified according to the American Clinical Neurophysiological Society critical care EEG terminology. Clinical outcome at discharge was dichotomized as good [Glasgow outcome scale (GOS) 4-5, low to moderate disability] vs. poor (GOS 1-3, severe disability to death).</AbstractText>Non-ventricular fibrillation/tachycardia arrest, longer time to ROSC, absence of brainstem reflexes, extensor or no motor response, lower pH, higher lactate, hypotension requiring >2 vasopressors, and absence of reactivity on EEG were all associated with poor outcome (all p values ≤ 0.01). Suppression-burst at any time indicated a poor prognosis, with a 0% false positive rate (FPR) [95% confidence interval (CI) 0-10%]. All patients (54/54) with suppression-burst or a low voltage (<20 µV) EEG at 24 h had a poor outcome, with an FPR of 0% [95% CI 0-8%]. Normal background voltage ≥ 20 µV without epileptiform discharges at any time interval carried a positive predictive value >70% for good outcome.</AbstractText>Suppression-burst or a low voltage at 24 h after ROSC was not compatible with good outcome in this series. Normal background voltage without epileptiform discharges predicted a good outcome.</AbstractText> |
10,749 | Two cases of cardiac sarcoidosis in pregnant women with supraventricular arrhythmia. | We present two cases of cardiac sarcoidosis whose first presentation was in pregnancy. All findings confirmed the diagnosis of sarcoidosis with cardiac involvement in both patients. The first patient, a 37-year-old, presented with dizziness and atrial fibrillation at 16 weeks' gestation. Echocardiography revealed thickened interventricular septum with a speckled pattern. Cardiac MRI after delivery showed myocardial oedema/inflammation corresponding with the same regions with early enhancement and epicardial delayed enhancement in the basal to mid-inferoseptal and basal anterior left ventricular myocardial segments. Transbronchial biopsy revealed histology of scanty fragments of inflamed bronchial mucosa. The second patient, a 31-year-old, was 17 weeks pregnant when she presented with daily palpitations and shortness of breath. She had prolonged episodes of supraventricular tachycardia. Echocardiography revealed a speckled septal and right ventricular wall pattern. Cardiac MRI after delivery showed basal and mid-ventricular mesocardial and epicardial enhancement, most compatible with sarcoidosis. |
10,750 | [The Wearable Cardioverter-Defibrillator (WCD)]. | While the implantable cardioverter-defibrillator (ICD) has been proven to be the best choice for patients with long-term risk for sudden cardiac arrest/sudden cardiac death (SCA/SCD), the question is how to manage patients with only temporary risk, e.g., during the guidelines-recommended waiting period until the decision for an ICD can be made. These patient groups should be monitored around the clock to guarantee a lifesaving shock within a few minutes, if necessary.These conditions can be accomplished by the wearable cardioverter-defibrillator (WCD) in the outpatient sector. The WCD is worn on the skin and consists of four nonadhesive ECG electrodes as well as three defibrillation electrodes-two at the back and one at the front-embedded in a garment. The defibrillation unit is connected via a cord and can be worn over the shoulder or on a belt. Cardiac events can be recorded and retrospectively analyzed by the treating physician.The WCD is a safe and effective measure to terminate potentially lethal ventricular tachycardia and ventricular fibrillation. It may be used early after myocardial infarction with reduced left ventricular ejection fraction (LVEF), as well as for patients with acute heart failure in nonischemic cardiomyopathy with uncertain cause and prognosis. In addition, it may be used for patients waiting for heart transplantation, for patients who cannot be implanted an ICD due to comorbidities, and for patients after explantation of their ICD, e.g., because of infection until reimplantation.One may expect that risk stratification of patients with the WCD will lead to even better selection for ICD use. |
10,751 | Neuromuscular comorbidity, heart failure, and atrial fibrillation as prognostic factors in left ventricular hypertrabeculation/noncompaction.<Pagination><StartPage>906</StartPage><EndPage>911</EndPage><MedlinePgn>906-11</MedlinePgn></Pagination><ELocationID EIdType="doi" ValidYN="Y">10.1007/s00059-015-4310-7</ELocationID><Abstract><AbstractText Label="BACKGROUND" NlmCategory="BACKGROUND">There is some controversy concerning the prognosis of patients with left ventricular hypertrabeculation/noncompaction (LVHT). LVHT is frequently associated with neuromuscular disorders (NMDs). The aim of this study was to assess cardiac and neurological findings as predictors of mortality in patients with LVHT.</AbstractText><AbstractText Label="PATIENTS AND METHODS" NlmCategory="METHODS">The study included patients with LVHT diagnosed between June 1995 and January 2014 in one echocardiographic laboratory. They underwent a baseline cardiologic examination and were invited for a neurological examination. Between January and February 2014, their survival status was assessed.</AbstractText><AbstractText Label="RESULTS" NlmCategory="RESULTS">LVHT was diagnosed in 220 patients (68 female, aged 52 ± 17 years) with a prevalence of 0.35 %/year. During a follow-up of 72 ± 61 months, 65 patients died. The mortality was 5 %/year. A neurological investigation was performed on 173 patients (79 %) and revealed specific NMDs in 31 (14 %), NMD of unknown etiology in 103 (47 %), and normal findings in 39 (18 %) patients. In multivariate analysis, the predictors of mortality were increased age (p = 0.0001), presence of a specific NMD (p = 0.0062) or NMD of unknown etiology (p = 0.0062), heart failure NYHA III (p = 0.0396), atrial fibrillation (p = 0.0022), and sinus tachycardia (p = 0.0395).</AbstractText><AbstractText Label="CONCLUSIONS" NlmCategory="CONCLUSIONS">LVHT patients should undergo systematic neurological examinations. Whether an optimal therapy of heart failure and atrial fibrillation will improve the prognosis of LVHT patients needs to be addressed in further studies.</AbstractText></Abstract><AuthorList CompleteYN="Y"><Author ValidYN="Y"><LastName>Stöllberger</LastName><ForeName>Claudia</ForeName><Initials>C</Initials><AffiliationInfo><Affiliation>Krankenanstalt Rudolfstiftung, Juchgasse 25, 1030, Vienna, Austria. claudia.stoellberger@chello.at.</Affiliation></AffiliationInfo><AffiliationInfo><Affiliation>, Steingasse 31/18, 1030, Vienna, Austria. claudia.stoellberger@chello.at.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Blazek</LastName><ForeName>Gerhard</ForeName><Initials>G</Initials><AffiliationInfo><Affiliation>Hanusch Krankenhaus, Heinrich-Collin-Straße 30, 1140, Vienna, Austria.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Gessner</LastName><ForeName>Martin</ForeName><Initials>M</Initials><AffiliationInfo><Affiliation>Hanusch Krankenhaus, Heinrich-Collin-Straße 30, 1140, Vienna, Austria.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Bichler</LastName><ForeName>Katharina</ForeName><Initials>K</Initials><AffiliationInfo><Affiliation>Landesklinikum Mödling, Sr. Maria Restituta-Gasse 12, 2340, Mödling, Austria.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Wegner</LastName><ForeName>Christian</ForeName><Initials>C</Initials><AffiliationInfo><Affiliation>Vienna Institute of Demography of the Austrian Academy of Sciences, Wohllebengasse 12-14, 1040, Vienna, Austria.</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Finsterer</LastName><ForeName>Josef</ForeName><Initials>J</Initials><AffiliationInfo><Affiliation>Krankenanstalt Rudolfstiftung, Juchgasse 25, 1030, Vienna, Austria.</Affiliation></AffiliationInfo></Author></AuthorList><Language>eng</Language><PublicationTypeList><PublicationType UI="D016428">Journal Article</PublicationType></PublicationTypeList><ArticleDate DateType="Electronic"><Year>2015</Year><Month>05</Month><Day>05</Day></ArticleDate></Article><MedlineJournalInfo><Country>Germany</Country><MedlineTA>Herz</MedlineTA><NlmUniqueID>7801231</NlmUniqueID><ISSNLinking>0340-9937</ISSNLinking></MedlineJournalInfo><SupplMeshList><SupplMeshName Type="Disease" UI="C564690">Noncompaction of Left Ventricular Myocardium with Congenital Heart Defects</SupplMeshName></SupplMeshList><CitationSubset>IM</CitationSubset><MeshHeadingList><MeshHeading><DescriptorName UI="D000293" MajorTopicYN="N">Adolescent</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D000328" MajorTopicYN="N">Adult</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D017677" MajorTopicYN="N">Age Distribution</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D000368" MajorTopicYN="N">Aged</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D000369" MajorTopicYN="N">Aged, 80 and over</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D001281" MajorTopicYN="N">Atrial Fibrillation</DescriptorName><QualifierName UI="Q000175" MajorTopicYN="N">diagnosis</QualifierName><QualifierName UI="Q000401" MajorTopicYN="Y">mortality</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D001317" MajorTopicYN="N">Austria</DescriptorName><QualifierName UI="Q000453" MajorTopicYN="N">epidemiology</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D015897" MajorTopicYN="N">Comorbidity</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D005260" MajorTopicYN="N">Female</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D006330" MajorTopicYN="N">Heart Defects, Congenital</DescriptorName><QualifierName UI="Q000000981" MajorTopicYN="N">diagnostic imaging</QualifierName><QualifierName UI="Q000401" MajorTopicYN="Y">mortality</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D006333" MajorTopicYN="N">Heart Failure</DescriptorName><QualifierName UI="Q000175" MajorTopicYN="N">diagnosis</QualifierName><QualifierName UI="Q000401" MajorTopicYN="Y">mortality</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D006801" MajorTopicYN="N">Humans</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D015994" MajorTopicYN="N">Incidence</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D008297" MajorTopicYN="N">Male</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D008875" MajorTopicYN="N">Middle Aged</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D009468" MajorTopicYN="N">Neuromuscular Diseases</DescriptorName><QualifierName UI="Q000175" MajorTopicYN="N">diagnosis</QualifierName><QualifierName UI="Q000401" MajorTopicYN="Y">mortality</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D011379" MajorTopicYN="N">Prognosis</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D015203" MajorTopicYN="N">Reproducibility of Results</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D012307" MajorTopicYN="N">Risk Factors</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D012680" MajorTopicYN="N">Sensitivity and Specificity</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D017678" MajorTopicYN="N">Sex Distribution</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D016019" MajorTopicYN="N">Survival Analysis</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D013616" MajorTopicYN="N">Tachycardia, Sinus</DescriptorName><QualifierName UI="Q000175" MajorTopicYN="N">diagnosis</QualifierName><QualifierName UI="Q000401" MajorTopicYN="Y">mortality</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D014463" MajorTopicYN="N">Ultrasonography</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D055815" MajorTopicYN="N">Young Adult</DescriptorName></MeshHeading></MeshHeadingList><KeywordList Owner="NOTNLM"><Keyword MajorTopicYN="N">Cardiomyopathy</Keyword><Keyword MajorTopicYN="N">Hypertrabeculation</Keyword><Keyword MajorTopicYN="N">Neuromuscular disorders</Keyword><Keyword MajorTopicYN="N">Noncompaction</Keyword><Keyword MajorTopicYN="N">Prognosis</Keyword></KeywordList></MedlineCitation><PubmedData><History><PubMedPubDate PubStatus="received"><Year>2015</Year><Month>1</Month><Day>19</Day></PubMedPubDate><PubMedPubDate PubStatus="accepted"><Year>2015</Year><Month>3</Month><Day>22</Day></PubMedPubDate><PubMedPubDate PubStatus="revised"><Year>2015</Year><Month>2</Month><Day>22</Day></PubMedPubDate><PubMedPubDate PubStatus="entrez"><Year>2015</Year><Month>5</Month><Day>6</Day><Hour>6</Hour><Minute>0</Minute></PubMedPubDate><PubMedPubDate PubStatus="pubmed"><Year>2015</Year><Month>5</Month><Day>6</Day><Hour>6</Hour><Minute>0</Minute></PubMedPubDate><PubMedPubDate 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<PubmedArticle><MedlineCitation Status="MEDLINE" Owner="NLM"><PMID Version="1">25938619</PMID><DateCompleted><Year>2015</Year><Month>11</Month><Day>20</Day></DateCompleted><DateRevised><Year>2018</Year><Month>11</Month><Day>13</Day></DateRevised><Article PubModel="Electronic"><Journal><ISSN IssnType="Electronic">1940-087X</ISSN><JournalIssue CitedMedium="Internet"><Issue>98</Issue><PubDate><Year>2015</Year><Month>Apr</Month><Day>26</Day></PubDate></JournalIssue><Title>Journal of visualized experiments : JoVE</Title><ISOAbbreviation>J Vis Exp</ISOAbbreviation></Journal>A Rat Model of Ventricular Fibrillation and Resuscitation by Conventional Closed-chest Technique. | A rat model of electrically-induced ventricular fibrillation followed by cardiac resuscitation using a closed chest technique that incorporates the basic components of cardiopulmonary resuscitation in humans is herein described. The model was developed in 1988 and has been used in approximately 70 peer-reviewed publications examining a myriad of resuscitation aspects including its physiology and pathophysiology, determinants of resuscitability, pharmacologic interventions, and even the effects of cell therapies. The model featured in this presentation includes: (1) vascular catheterization to measure aortic and right atrial pressures, to measure cardiac output by thermodilution, and to electrically induce ventricular fibrillation; and (2) tracheal intubation for positive pressure ventilation with oxygen enriched gas and assessment of the end-tidal CO2. A typical sequence of intervention entails: (1) electrical induction of ventricular fibrillation, (2) chest compression using a mechanical piston device concomitantly with positive pressure ventilation delivering oxygen-enriched gas, (3) electrical shocks to terminate ventricular fibrillation and reestablish cardiac activity, (4) assessment of post-resuscitation hemodynamic and metabolic function, and (5) assessment of survival and recovery of organ function. A robust inventory of measurements is available that includes - but is not limited to - hemodynamic, metabolic, and tissue measurements. The model has been highly effective in developing new resuscitation concepts and examining novel therapeutic interventions before their testing in larger and translationally more relevant animal models of cardiac arrest and resuscitation. |
10,752 | Effects of the Selective Stretch-Activated Channel Blocker GsMtx4 on Stretch-Induced Changes in Refractoriness in Isolated Rat Hearts and on Ventricular Premature Beats and Arrhythmias after Coronary Occlusion in Swine. | Mechanical factors may contribute to ischemic ventricular arrhythmias. GsMtx4 peptide, a selective stretch-activated channel blocker, inhibits stretch-induced atrial arrhythmias. We aimed to assess whether GsMtx4 protects against ventricular ectopy and arrhythmias following coronary occlusion in swine. First, the effects of 170-nM GsMtx4 on the changes in the effective refractory period (ERP) induced by left ventricular (LV) dilatation were assessed in 8 isolated rat hearts. Then, 44 anesthetized, open-chest pigs subjected to 50-min left anterior descending artery occlusion and 2-h reperfusion were blindly allocated to GsMtx4 (57 μg/kg iv. bolus and 3.8 μg/kg/min infusion, calculated to attain the above concentration in plasma) or saline, starting 5-min before occlusion and continuing until after reflow. In rat hearts, LV distension induced progressive reductions in ERP (35±2, 32±2, and 29±2 ms at 0, 20, and 40 mmHg of LV end-diastolic pressure, respectively, P<0.001) that were prevented by GsMTx4 (33±2, 33±2, and 32±2 ms, respectively, P=0.002 for the interaction with LV end-diastolic pressure). Pigs receiving GsMtx4 had similar number of ventricular premature beats during the ischemic period as control pigs (110±28 vs. 103±21, respectively, P=0.842). There were not significant differences among treated and untreated animals in the incidence of ventricular fibrillation (13.6 vs. 22.7%, respectively, P=0.696) or tachycardia (36.4 vs. 50.0%, P=0.361) or in the number of ventricular tachycardia episodes during the occlusion period (1.8±0.7 vs. 5.5±2.6, P=0.323). Thus, GsMtx4 administered under these conditions does not suppress ventricular ectopy following coronary occlusion in swine. Whether it might protect against malignant arrhythmias should be tested in studies powered for these outcomes. |
10,753 | Cardiac magnetic resonance for prediction of arrhythmogenic areas. | Catheter ablation has been widely used to manage recurrent atrial and ventricular arrhythmias. It has been established that contrast-enhanced magnetic resonance can accurately characterize the myocardium. In this review, we summarize the role of cardiac magnetic resonance in identification of arrhythmogenic substrates, and the potential utility of cardiac magnetic resonance for catheter ablation of complex atrial and ventricular arrhythmias. |
10,754 | Managing cardiac arrest with refractory ventricular fibrillation in the emergency department: Conventional cardiopulmonary resuscitation versus extracorporeal cardiopulmonary resuscitation. | Refractory ventricular fibrillation, resistant to conventional cardiopulmonary resuscitation (CPR), is a life threatening rhythm encountered in the emergency department. Although previous reports suggest the use of extracorporeal CPR can improve the clinical outcomes in patients with prolonged cardiac arrest, the effectiveness of this novel strategy for refractory ventricular fibrillation is not known. We aimed to compare the clinical outcomes of patients with refractory ventricular fibrillation managed with conventional CPR or extracorporeal CPR in our institution.</AbstractText>This is a retrospective chart review study from an emergency department in a tertiary referral medical center. We identified 209 patients presenting with cardiac arrest due to ventricular fibrillation between September 2011 and September 2013. Of these, 60 patients were enrolled with ventricular fibrillation refractory to resuscitation for more than 10 min. The clinical outcome of patients with ventricular fibrillation received either conventional CPR, including defibrillation, chest compression, and resuscitative medication (C-CPR, n = 40) or CPR plus extracorporeal CPR (E-CPR, n = 20) were compared.</AbstractText>The overall survival rate was 35%, and 18.3% of patients were discharged with good neurological function. The mean duration of CPR was longer in the E-CPR group than in the C-CPR group (69.90 ± 49.6 min vs 34.3 ± 17.7 min, p = 0.0001). Patients receiving E-CPR had significantly higher rates of sustained return of spontaneous circulation (95.0% vs 47.5%, p = 0.0009), and good neurological function at discharge (40.0% vs 7.5%, p = 0.0067). The survival rate in the E-CPR group was higher (50% vs 27.5%, p = 0.1512) at discharge and (50% vs 20%, p = 0. 0998) at 1 year after discharge.</AbstractText>The management of refractory ventricular fibrillation in the emergency department remains challenging, as evidenced by an overall survival rate of 35% in this study. Patients with refractory ventricular fibrillation receiving E-CPR had a trend toward higher survival rates and significantly improved neurological outcomes than those receiving C-CPR.</AbstractText>Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.</CopyrightInformation> |
10,755 | Femoral venous oxygen saturation obtained during CPR predicts successful resuscitation in a pig model. | Central venous oxygen saturation has been shown to reflect the adequacy of tissue oxygenation during cardiopulmonary resuscitation (CPR), thereby enabling the assessment of CPR quality and the prediction of restoration of spontaneous circulation (ROSC). The femoral vein can be easily accessed during CPR. We determined if femoral venous oxygen saturation (SFVO2) values obtained during CPR could reliably predict ROSC in a pig model.</AbstractText>After 15 minutes of untreated ventricular fibrillation followed by 8 minutes of basic life support, 19 pigs underwent advanced cardiovascular life support. During advanced cardiovascular life support, femoral venous blood samples were obtained at 4-minute intervals. The abilities of SFVO2 and coronary perfusion pressure (CPP) to predict ROSC were evaluated by calculating the areas under receiver operating characteristic curves (AUCs).</AbstractText>Eight pigs (42.1%) achieved ROSC. The resuscitated animals had significantly higher CPP (P < .001) and SFVO2 (P < .001) values than the nonresuscitated animals, and there was a significant correlation between SFVO2 and CPP values (r = 0.684; P < .001). The CPPs of the resuscitated and nonresuscitated animals overlapped considerably; however, there was minimal overlap between the 2 groups for SFVO2. Femoral venous oxygen saturation significantly predicted ROSC with an AUC of 0.997 (95% confidence interval, 0.911-1.000; P < .001), and it had a larger AUC than CPP (AUC, 0.964; 95% confidence interval, 0.855-0.997; P < .001). The AUC difference, however, was not statistically significant (P = .157).</AbstractText>In this study, SFVO2 values obtained during CPR exhibited a significant correlation with CPP and reliably predicted ROSC.</AbstractText>Copyright © 2015 Elsevier Inc. All rights reserved.</CopyrightInformation> |
10,756 | Impact of Concomitant Tricuspid Annuloplasty on Tricuspid Regurgitation, Right Ventricular Function, and Pulmonary Artery Hypertension After Repair of Mitral Valve Prolapse. | For patients undergoing mitral valve (MV) repair, the indications for and results of concomitant tricuspid annuloplasty remain controversial.</AbstractText>This study was designed to compare a strategy of routine concomitant tricuspid annuloplasty for moderate tricuspid regurgitation (TR) or tricuspid annular dilation in patients undergoing degenerative MV surgery.</AbstractText>Of 645 consecutive patients (mean age 57±13 years) undergoing primary repair of degenerative mitral regurgitation between 2003 and 2011, 419 (65%) underwent concomitant tricuspid annuloplasty for moderate TR and/or tricuspid annular dilation. These patients were retrospectively analyzed with longitudinal echocardiographic follow-up.</AbstractText>Patients undergoing tricuspid valve repair were older (mean age 59.2 years vs. 52.3 years), had worse right and left ventricular function and higher pulmonary artery pressures, and were more likely to have had atrial fibrillation than patients undergoing isolated MV repair (all p<0.05). No significant difference in 30-day mortality, morbidity, or permanent pacemaker requirement was seen between treatment groups. Freedom from moderate TR at 7 years was not significantly different in the 2 groups, but multivariate analysis showed that tricuspid annuloplasty was independently associated with freedom from late moderate TR (p=0.04), and was an independent predictor of recovery of right ventricular function (p=0.02).</AbstractText>In patients with moderate TR or tricuspid annular dilation who were undergoing degenerative mitral repair, concomitant tricuspid annuloplasty is safe, effective, and associated with improved long-term right-sided remodeling. Routine treatment of moderate TR or tricuspid annular dilation at the time of MV repair appears to be beneficial.</AbstractText> |
10,757 | Right ventricular hypertrophy is associated with cardiovascular events in hypertrophic cardiomyopathy: evidence from study with magnetic resonance imaging. | Although left ventricular (LV) morphology and function have been well studied in hypertrophic cardiomyopathy (HCM), few data exist regarding the right ventricle. Accordingly, we studied right ventricular (RV) morphology and function and their effect on cardiovascular events in HCM using cardiac magnetic resonance (CMR) imaging.</AbstractText>This retrospective study included 106 HCM patients (age 61.6 ± 14.5 years) examined using CMR imaging during January 2008 to September 2014. RV hypertrophy (RVH) was defined as RV maximal wall thickness > 5 mm.</AbstractText>RVH was observed in 30 of the 106 patients (RVH group), with the remaining 76 patients assigned to the non-RVH group. The RVH group had higher brain natriuretic peptide levels (461.6 ± 699.8 pg/mL vs. 225.3 ± 254.5 pg/mL; P = 0.01) and also showed a reduced RV end-diastolic volume index (43.4 ± 16.0 mL/m2 vs. 56.6±15.2 mL/m2; P = 0.0001), in keeping with a greater LV mass index (109.1 ± 24.9 g/m2 vs. 78.6 ± 23.0 g/m2; P < 0.0001). The RVH group was prominently associated with RV late gadolinium enhancement compared with the non-RVH group (33.3% vs. 0%; P < 0.0001). After CMR imaging, 15 patients developed cardiovascular events that included admission for heart failure, ventricular tachyarrhythmia/fibrillation, stroke, and sudden cardiac death. Cox proportional hazard analysis revealed that RVH was an independent predictor of the occurrence of cardiovascular events after adjustments by sex, age, LV mass index, LV ejection fraction, and LV outflow tract obstruction (hazard ratio, 5.42; 95% confidence interval, 1.16-25.3; P = 0.03).</AbstractText>These results suggest that HCM patients with RVH on CMR images have a greater incidence of cardiovascular events than non-RVH patients. Further work is needed to confirm this observation and assess its clinical importance.</AbstractText>Copyright © 2015 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
10,758 | Therapeutic hypothermia in patients with out-of-hospital arrest. | Therapeutic hypothermia (TH) is increasingly used in patients presenting with out-of-hospital cardiac arrest (OHCA). Such strategies derive from data that suggest TH may improve survival and attenuate adverse neurological outcomes associated with the cardiac arrest. Consequently, TH has been integrated into various guidelines for the management of OHCA and has become a focussed strategy, particularly in patients with ST-segment elevation myocardial infarction. However, there remains uncertainty over the true impact of TH. In patients with OHCA due to asystole or pulseless electrical activity, overall available evidence suggests that TH does not improve neurological outcomes and survival. While in patients with OHCA due to ventricular fibrillation or ventricular tachycardia, observational studies and small, randomised studies have suggested there may be survival benefits and improved neurological recovery. However, even here, trial data robustness has been questioned, with ongoing debate regarding the optimum temperature for managing patients with OHCA and optimal timing of its initiation. More uniform and robust guidelines for the application of TH for patients with OHCA are required, but can only be formulated on appropriately sized robust trials. This review examines the current status of TH. |
10,759 | Detection of left atrial thrombus by intracardiac echocardiography in patients undergoing ablation of atrial fibrillation. | The role of intracardiac echocardiography (ICE) to detect thrombus within left atrium (LA) before atrial fibrillation (AF) ablation despite a recent transesophageal echocardiogram (TEE) is not well defined. We examined the prevalence of LA/left atrial appendage (LAA) thrombus using ICE immediately prior to AF ablation in patients in whom anticoagulation was not withheld.</AbstractText>We analyzed 122 consecutive patients (62.6 ± 10.8 years, 90 males, CHA(2)DS(2) -VASc score 2.4 ± 1.5, persistent AF 29.5 %) who underwent an ICE-guided AF ablation 1 day after a negative (n = 120) or inconclusive (n = 2) TEE for LA thrombus. LA was imaged with ICE from the right atrium, coronary sinus, and right ventricular inflow tract (RVIT). ICE and TEE images were compared for LAA area, thrombus, and spontaneous echo contrast (SEC).</AbstractText>LAA was adequately visualized in 99 and 100 % of patients with TEE and ICE, respectively. RVIT was the best ICE view for LAA visualization. The LAA 2-D-area measured by TEE was 4.9 ± 0.5 vs. 5 ± 0.5 cm(2) by ICE (P = NS). ICE identified a thrombus in seven patients with a previous negative TEE, leading to cancellation of ablation. It ruled out a thrombus in two patients with an inconclusive TEE. Thrombi were found in the LAA (n = 4), atrial septum (n = 2), and left superior pulmonary vein (n = 1). SEC during TEE was more frequent in patients with thrombus on ICE than those without (85.7 vs. 17.4 %; p = 0.03; positive predictive value 23.1 %, negative predictive value 98.9 %).</AbstractText>The results of our staged imaging approach suggest that ICE has a complimentary value in re-screening the LA/LAA for thrombus after a recent negative or equivocal TEE. The presence of SEC during TEE increases the probability of finding a thrombus with ICE, which could potentially be dislodged during catheter manipulation.</AbstractText> |
10,760 | Secondary ventricular fibrillation or pulseless ventricular tachycardia during cardiac arrest and epinephrine dosing. | Development of ventricular fibrillation or pulseless ventricular tachycardia after an initial rhythm of pulseless electrical activity or asystole is associated with significantly increased cardiac arrest mortality.</AbstractText>To examine differences in epinephrine administration during cardiac arrest between patients who had a secondary ventricular fibrillation or ventricular tachycardia develop and patients who did not.</AbstractText>Data were collected for 2 groups of patients with in-hospital cardiac arrest and an initial rhythm of pulseless electrical activity or asystole: those who had a secondary ventricular fibrillation or ventricular tachycardia develop (cases) and those who did not (controls). Dosing of epinephrine during cardiac arrest and other variables were compared between cases and controls.</AbstractText>Of the 215 patients identified with an initial rhythm of pulseless electrical activity or asystole, 51 (23.7%) had a secondary ventricular fibrillation or ventricular tachycardia develop. Throughout the total duration of arrest, including periods of return of spontaneous circulation, the dosing interval for epinephrine in patients who had a secondary ventricular fibrillation or ventricular tachycardia develop was 1 mg every 3.4 minutes compared with 1 mg every 5 minutes in controls (P= .001). For the total duration of pulselessness, excluding periods of return of spontaneous circulation during the arrest, the dosing interval for epinephrine in patients who had a secondary ventricular fibrillation or ventricular tachycardia develop was 1 mg every 3.1 minutes versus 1 mg every 4.3 minutes in controls (P= .001).</AbstractText>More frequent administration of epinephrine during cardiac arrest is associated with development of secondary ventricular fibrillation or ventricular tachycardia.</AbstractText>©2015 American Association of Critical-Care Nurses.</CopyrightInformation> |
10,761 | Meta-Analysis on Risk Stratification of Asymptomatic Individuals With the Brugada Phenotype. | The prognosis of asymptomatic subjects remains the most controversial issue in Brugada syndrome (BS). A meta-analysis on the prognostic role of spontaneous type 1 electrocardiographic (ECG) pattern and programmed ventricular stimulation (PVS) in asymptomatic subjects with Brugada electrocardiogram was performed. Current databases were searched until March 2014. Fourteen prospective observational studies were included in the present meta-analysis, accumulating data on 3,536 asymptomatic subjects (2,820 men) with BS phenotype. The mean follow-up period varied from 20 and 77 months. Data regarding 1,398 asymptomatic subjects with spontaneous type 1 ECG pattern of BS were retrieved from 6 studies. During follow-up, arrhythmic events (sustained ventricular tachycardia/fibrillation, appropriate device therapies, or arrhythmic death) occurred in 42 patients (3%). The meta-analysis of these studies demonstrated that asymptomatic subjects with spontaneous type 1 ECG pattern of BS exhibit an increased risk of future arrhythmic events (odds ratio = 3.56, 95% confidence interval 1.70 to 7.47, Z = 3.37, p = 0.0008); 1,104 asymptomatic subjects with BS ECG pattern from 12 studies underwent PVS and were available for analysis. During follow-up, arrhythmic events occurred in 36 subjects (3.3%). Inducible ventricular arrhythmias at PVS were predictive of future arrhythmic events (odds ratio = 3.51, 95% confidence interval 1.60 to 7.67, Z = 3.14, p = 0.002). In conclusion, this meta-analysis showed that asymptomatic subjects with either spontaneous diagnostic ECG pattern or inducible ventricular arrhythmias at PVS are at increased risk. |
10,762 | Pre-shock chest compression pause effects on termination of ventricular fibrillation/tachycardia and return of organized rhythm within mechanical and manual cardiopulmonary resuscitation. | Shorter manual chest compression pauses prior to defibrillation attempts is reported to improve the defibrillation success rate. Mechanical load-distributing band (LDB-) CPR enables shocks without compression pause. We studied pre-shock pause and termination of ventricular fibrillation/pulseless ventricular tachycardia 5s post-shock (TOF) and return of organized rhythm (ROOR) with LDB and manual (M-) CPR.</AbstractText>In a secondary analysis from the Circulation Improving Resuscitation Care trial, patients with initial shockable rhythm and interpretable post-shock rhythms were included. Pre-shock rhythm, pause duration (if any), and post-shock rhythm were obtained for each shock. Associations between TOF/ROOR and pre-shock pause duration, including no pause shocks with LDB-CPR, were analyzed with Chi-square test. A p-value <0.05 was considered statistically significant.</AbstractText>For TOF and ROOR analyses we included 417 LDB-CPR patients with 1476 and 1438 shocks, and 495 M-CPR patients with 1839 and 1796 shocks, respectively. For first shocks with LDB-CPR, pre-shock pause was associated with TOF (p=0.049) with lowest TOF (77%) for shocks given without pre-shock compression pause. This association was not significant when all shocks were included (p=0.07) and not for ROOR. With M-CPR there were no significant associations between shock-related chest compression pause duration and TOF or ROOR.</AbstractText>For first shocks with LDB-CPR, termination of fibrillation was associated with pre-shock pause duration. There was no association for the rate of return of organized rhythm. For M-CPR, where no shocks were given during continuous chest compressions, there were no associations between pre-shock pause duration and TOF or ROOR.</AbstractText>Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
10,763 | Time course of appropriate implantable cardioverter-defibrillator therapy and implications for guideline-based driving restrictions. | American Heart Association/Heart Rhythm Society recommendations restrict driving in implantable cardioverter-defibrillator patients for 6 months after implant for secondary prevention or primary prevention with an appropriate therapy (antitachycardia pacing or shock) for ventricular arrhythmias (VA).</AbstractText>The purpose of this study was to analyze implantable cardioverter-defibrillator therapy data to inform guideline recommendations on driving.</AbstractText>The OMNI Registry was queried for VA and assessed for the time course of appropriate therapies. A blind events committee adjudicated events. The Kaplan-Meier method was used to estimate event rates. A 7-day blanking period was used for each event of interest.</AbstractText>A total of 2262 patients (mean age 67 ± 12 years; mean left ventricular ejection fraction 28%) were enrolled; 1659 (73%) were men, and 1666 (74%) were implanted for primary prevention. Overall, 628 of 2255 patients (28%) received ≥1 appropriate therapy. The probability of receiving a subsequent appropriate therapy increased and occurred in a shorter time interval with each appropriate therapy. At 6 months, the likelihood of receiving a shock when the first VA was terminated by shock (30.0%) was 3 times the risk when the first VA was terminated by antitachycardia pacing (9.9%).</AbstractText>Each appropriate VA therapy is associated with an increased risk of a subsequent event that occurs, on average, in a time frame shorter than current guideline-based restrictions. A differential risk of shock is noted in those receiving antitachycardia pacing vs shock for the first appropriate VA. These findings may help to inform future clinical guideline and practice decisions related to driving.</AbstractText>Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
10,764 | Brugada Syndrome: An Electrical Storm without Warning. | Brugada Syndrome (BrS) is an inherited channelopathy causing sodium channel dysfunction in cardiac myocyte. These patients are prone to develop Ventricular Fibrillation (VF) or polymorphic Ventricular Tachycardia (VT). Next to coronary artery disease and cardiomyopathies, BrS is an important cause of sudden cardiac death. We report here a case of 22 year unmarried female with "unexplained" cardiac arrest without prior history of syncope and family history of sudden cardiac death. She was resuscitated out of hospital in some local dispensary in rural settings and after prolonged hypoxia with its neurological sequelae, she eventually died. BrS should be considered in differentials of unexplained cardiac arrest even in patients without family history of sudden cardiac death. First episode of VT/VF in BrS patients can be life threatening. Only prompt cardioversion / defibrillation can save life. We have suggested some measures to identify patients of BrS. |
10,765 | Influence of baseline ejection fraction on the prognostic value of paravalvular leak after transcatheter aortic valve implantation. | Moderate or severe paravalvular leak (PVL ≥ moderate) after transcatheter aortic valve implantation (TAVI) is associated with poor outcomes. The aim of this study was to assess whether the baseline ejection fraction (EF) affects the impact of PVL on mortality after TAVI.</AbstractText>We analyzed 514 consecutive patients with native severe aortic stenosis who underwent TAVI. Patients were divided into two groups: EF < 40% group (n = 84) and EF ≥ 40% group (n = 430) according to baseline EF.</AbstractText>The mean age was 79.5 years and 49% were male. Patients in the EF < 40% group were younger and with higher logistic EuroSCORE compared to patients in the EF ≥ 40% group. Diabetes, coronary artery disease, atrial fibrillation and renal insufficiency were more prevalent in the EF < 40% group. Patients in the EF <40% group had more mitral regurgitation. In-hospital mortality was significantly higher in the EF < 40% group (8.3% vs. 0.9%, p < 0.0001). PVL ≥ moderate was significantly associated with increased 2-year estimated mortality only in the EF <40% group (65% vs. 20%, log-rank p < 0.0001) whereas no difference was seen in the EF ≥40% group (24% vs. 19%, log-rank p = 0.509). Interaction between PVL ≥ moderate and EF < 40% was statistically significant.</AbstractText>The impact of PVL ≥ moderate on mortality after TAVI was significant in the EF <40% group but not in the EF ≥ 40% group in our study. Even though operators should aim to minimize PVL in all TAVI patients, special attention is required for patients with reduced baseline EF.</AbstractText>Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
10,766 | Sex Differences in Device Therapies for Ventricular Arrhythmias or Death in the Multicenter Automatic Defibrillator Implantation Trial With Cardiac Resynchronization Therapy (MADIT-CRT) Trial. | Studies suggest that women with ischemic heart disease are less likely to experience appropriate ICD therapies for ventricular arrhythmias (VT/VF). We evaluated the influence of sex on arrhythmic events or death in subjects enrolled in MADIT-CRT.</AbstractText>Arrhythmic event rates, defined as VT/VF treated with defibrillator therapy or all-cause death, were determined among 1,790 subjects enrolled in MADIT-CRT with documented 3-year follow-up. Predictors of VT/VF/death were identified using multivariate analysis. Ninety-one (21%) women and 466 (35%) men experienced VT/VF/death over the follow-up period. The overall probability of VT/VF/death was significantly lower in women versus men (HR 0.62; P < 0.001). The probability of VT/VF/death was the lowest in women with ischemic heart disease (HR 0.51; P = 0.003). In ICD subjects, the 3-year risk of VT/VF was lower in ischemic women versus men (P = 0.021), and in nonischemic women versus men (P = 0.049). The probability of VT/VF/death was significantly lower in women (HR 0.52; P = 0.007) and men (HR 0.74; P = 0.018) with LBBB who received CRT-D. Appropriate shock therapy strongly correlated with increased risk of death during postshock follow-up in women (HR 5.18; P = 0.001) and men (HR 1.63; P = 0.033); interaction P value of 0.034.</AbstractText>In this substudy of MADIT-CRT, sex, etiology of heart disease and type of device implanted significantly influenced subsequent risk for VT/VF or death. Women with ischemic heart disease and women with LBBB who received CRT-D had the lowest incidence of VT/VF or death when compared to men. Appropriate shock therapy was a strong predictor of death, particularly in women.</AbstractText>© 2015 Wiley Periodicals, Inc.</CopyrightInformation> |
10,767 | The number of prehospital defibrillation shocks and 1-month survival in patients with out-of-hospital cardiac arrest. | The relationship between the number of pre-hospital defibrillation shocks and treatment outcome in patients with out-of-hospital cardiac arrest (OHCA) presenting with ventricular fibrillation (VF) is unknown currently. We examined the association between the number of pre-hospitalization defibrillation shocks and 1-month survival in OHCA patients.</AbstractText>We conducted a prospective observational study using national registry data obtained from patients with OHCA between January 1, 2009 and December 31, 2012 in Japan. The study subjects were ≥ 18-110 years of age, had suffered from an OHCA before arrival of EMS personnel, had a witnessed collapse, had an initial rhythm that was shockable [VF/ventricular tachycardia (pulseless VT)], were not delivered a shock using a public automated external defibrillator (AED), received one or more shocks using a biphasic defibrillator by EMS personnel, and were transported to a medical institution between January 1, 2009 and December 31, 2012. There were 20,851 OHCA cases which met the inclusion criteria during the study period. Signal detection analysis was used to identify the cutoff point in the number of prehospital defibrillation shocks most closely related to one-month survival. Variables related to the number of defibrillations or one-month survival in OHCA were identified using multiple logistic regression analysis.</AbstractText>A cutoff point in the number of pre-hospital defibrillation shocks most closely associated with 1-month OHCA survival was between two and three (χ(2) = 209.61, p < 0.0001). Among those patients who received two shocks or less, 34.48% survived for at least 1 month, compared with 24.75% of those who received three shocks or more. The number of defibrillations (odds ratio [OR] = 1.19, 95% CI: 1.03, 1.38), OHCA origin (OR = 2.81, 95% CI: 2.26, 3.49), use of ALS devices (OR = 0.68, 95% CI: 0.59, 0.79), use of epinephrine (OR = 0.33, 95% C: 0.28, 0.39), interval between first defibrillation and first ROSC (OR = 1.45, 95% CI: 1.18, 1.78), and chest compression (OR = 1.21, 95% CI: 1.06, 1.38) were associated significantly with 1-month OCHA survival.</AbstractText>The cutoff point in the number of defibrillations of patients with OHCA most closely related to one-month survival was between 2 and 3, and the likelihood of non-survival 1 month after an OHCA was increased when ≥3 shocks were needed. Further studies are needed to verify this finding.</AbstractText> |
10,768 | Extracorporeal membrane oxygenation after protracted ventricular fibrillation cardiac arrest: case report and discussion. | Extracorporeal membrane oxygenation (ECMO) is a method to provide temporary cardiac and respiratory support to critically ill patients. In recent years, the role of ECMO in emergency departments (EDs) for select adults has increased. We present the dramatic case of a 29-year-old man who was placed on venoarterial ECMO for cardiogenic shock and respiratory failure following collapse and protracted ventricular fibrillation cardiac arrest in our ED. Resuscitation efforts prior to ECMO commencement included 49 minutes of virtually continuous cardiopulmonary resuscitation (CPR), 11 defibrillations, administration of numerous medications, including a thrombolytic agent, while CPR was ongoing, percutaneous coronary intervention and stenting for a mid-left anterior descending coronary artery dissection and thrombotic occlusion, inotropic support, and intra-aortic balloon pump counterpulsation. Over the next 48 hours following ECMO commencement, the patient's cardiorespiratory function rapidly improved, and he was discharged home 9 days after admission with no neurologic sequelae. The history, indications, and increasing role of ECMO in a range of conditions, including cardiac arrest, are reviewed. |
10,769 | Different Impacts of Time From Collapse to First Cardiopulmonary Resuscitation on Outcomes After Witnessed Out-of-Hospital Cardiac Arrest in Adults. | It is well known that cardiopulmonary resuscitation (CPR) should be attempted as early as possible after out-of-hospital cardiac arrest (OHCA). However, it is unclear about the impact of time to CPR on OHCA outcome by first documented rhythm (pulseless ventricular tachycardia/ventricular fibrillation [pVT/VF], pulseless electric activity [PEA], and asystole).</AbstractText>We enrolled 257,354 adult witnessed OHCA patients between 2007 and 2012 from a prospective nationwide population-based cohort database in Japan. We evaluated relationships between time from collapse to first CPR and neurologically favorable 1-month survival defined as Glasgow-Pittsburg cerebral performance category 1 or 2 by first documented rhythm after witnessed OHCA. We used logistic model for the estimation of prognosis. The number of OHCA patients with pVT/VF, PEA, and asystole were 38,661, 96,906, and 121,787, respectively. The overall neurologically favorable 1-month survival rates were 21.3% in patients with pVT/VF, 2.7% PEA, and 0.6% asystole. The proportion of asystole increased as the time from collapse to CPR delayed, whereas those of pVT/VF and PEA decreased (trend P<0.001). Estimated incidences of end-point after OHCA became lower as first CPR delayed irrespective of type of first documented rhythm, but were different by the rhythm. The average percentage point decreases in neurologically favorable 1-month survival probability for each incremental minute of CPR delay were 8.3%, 4.4%, and 6.4% for patients with pVT/VF, PEA, and asystole, respectively.</AbstractText>The OHCA outcome differed by time to first CPR and first documented rhythm. Shortening of time to first CPR is crucial for improving the OHCA outcome.</AbstractText>© 2015 American Heart Association, Inc.</CopyrightInformation> |
10,770 | ECG Patterns In Cardiac Resynchronization Therapy. | Cardiac resynchronization therapy is an established treatment modality in heart failure. Though non-response is a serious issue. To address this issue, a good understanding of the electrical activation during underlying intrinsic ventricular activation, biventricular as well as right- and left ventricular pacing is needed. By interpreting the 12-lead electrocardiogram, possible reasons for suboptimal treatment can be identified and addressed. This article reviews the literature on QRS morphology in cardiac resynchronization therapy and its role in optimization of therapy. |
10,771 | Conjoined Inferior Pulmonary Veins during Pulmonary Vein Isolation: Prevalence and Novel Approach for Pulmonary Vein Isolation with Cryoballoon. | Cardiac resynchronization therapy is an established treatment modality in heart failure. Though non-response is a serious issue. To address this issue, a good understanding of the electrical activation during left bundle branch block, biventricular, as well as right- and left ventricular pacing is needed. This way by interpreting the 12-lead electrocardiogram, possible reasons for suboptimal treatment can be identified and addressed. This article reviews the literature on QRS morphology in cardiac resynchronization therapy and its meaning in optimization of therapy. |
10,772 | Optimizing CRT - Do We Need More Leads and Delivery Methods. | Cardiac resynchronization therapy (CRT) is an established therapeutic option in symptomatic heart failure with reduced ejection fraction and evidence of left ventricular (LV) conduction delay (QRS width ≥120 ms), especially when typical left bundle branch block is present. The rationale behind CRT is restoration of aberrant LV electrical activation. As there is considerable heterogeneity of the LV electrical activation pattern among CRT candidates, an individualized approach with targeting of the LV lead in the region of latest electrical activation while avoiding scar tissue may enhance CRT response. Echocardiography, electro anatomic mapping, and cardiac magnetic resonance imaging with late gadolinium enhancement are helpful to guide such targeted LV lead placement. However, an important limitation remains the anatomy of the coronary sinus, which often does not allow concordant LV lead placement in the optimal region. Epicardial LV lead placement through minimal invasive surgery or endocardial LV lead placement through transseptal punction may overcome this limitation, obviously with an increased complication risk. Furthermore, recent pacing algorithms suggest superiority of LV-only versus biventricular pacing in patients with preserved atrio ventricular (AV) conduction and a typical LBBB pattern. Finally, pacing from only one LV site might not overcome the wide electrical dispersion often seen in patients with LV conduction delays. Therefore, multisite pacing has gained significant interest to improve CRT response. The use of multiple LV leads may potentially lead to more favorable reverse remodeling, improved functional capacity and quality of life in CRT candidates, but adverse events and a shorter battery span are more frequent because of the extra lead. The use of one multipolar LV lead increases the number of pacing configurations within the same coronary sinus side branch (within small distances from each other) without the use of an additional lead. Small observational studies suggest that more effective resynchronization can be achieved with this approach. Finally, there are many reasons for non effective CRT delivery in carefully selected patients with an adequately implanted device. Multidisciplinary, post implantation care inside a dedicated CRT clinic ensures optimal CRT delivery, improves response rate and should be considered standard of care. |
10,773 | How To Identify & Treat Epicardial Origin Of Outflow Tract Tachycardias. | The right ventricle outflow tract (RVOT) is the most common site of origin of idiopathic ventricular arrhythmias. The typical outflow tract arrhythmias pattern on ECG is an inferior axis deviation and left bundle branch block when originated on the RVOT and right bundle branch block morphology when originated on the left ventricular outflow tract (LVOT). There are several ECG tricks for different locations of origin. An increased Maximum Deflection Index (MDI) suggests epicardial origin of arrhythmia. In general the result of ablation is very good, but sometimes there are difficult and unsuccessful procedures. The origin in the aortic cusps and epicardium are the reason for failure in some cases. When they are epicardial, the arrhythmias can be accessed by the venous system or by subxiphoid epicardial mapping. |
10,774 | A Questionable Indication For ICD Extraction After Successful VT Ablation. | Sustained ventricular tachyarrhythmias represent a kind of complication shared by a number of clinical presentations of heart disease, sometimes leading to sudden cardiac death. Many efforts have been made in the fight against such a complication, mainly being represented by the implantable cardioverter defibrillator (ICD). In recent years, catheter ablation has grown as a means to effectively treat patients with sustained ventricular arrhythmias, in the contest of different cardiac substrates. Since carrying an ICD is associated with a potential risk deriving from its possible infective or malfunctioning complications, and given the current effectiveness of lead extraction procedures, it has been thought not to be unreasonable to ask ourselves about how to deal with ICD patients who have been successfully treated by means of ablation of their ventricular arrhythmias. To date, no control data have been published on transvenous lead extraction in the setting of VT ablation. In this paper we will review the current evidence about ICD therapy, catheter ablation of ventricular arrhythmias and lead extraction, trying to outline some considerations about how to face this new clinical issue. |
10,775 | [The automated external defibrillator in the resuscitation chain. The importance of the AED examined]. | The survival rate for those suffering an out-of-hospital cardiac arrest (OHCA) is improving slowly, with > 90% of the survivors being discharged from hospital with cognitive function intact. A recent analysis of the ARREST (AmsteRdam Resuscitation Study) group documented an increase in survival rates with favourable neurological outcome from 16.2% in 2006 to 19.7% in 2012. Only those victims whose initial cardiac rhythm is 'shockable' (i.e. ventricular fibrillation or tachycardia) reap the benefits: their survival rate increased from 29.1% to 41.4%. The prognosis for those with a non-shockable rhythm remains grim (< 5% survival). A recent analysis of the ARREST database points to the increasing use of AEDs (by laypersons, but particularly by police officers and fire-fighters with a training in basic life support) as one of the main drivers of this improved prognosis. An AED is now used in 59% of OHCA in the greater Amsterdam area, and has become an essential link in the resuscitation chain. |
10,776 | The Past, Present, and Potential Future of Sodium Channel Block as an Atrial Fibrillation Suppressing Strategy. | Despite major advances in arrhythmia therapy, atrial fibrillation (AF) remains a challenge. A significant limitation in AF management is the lack of safe and effective drugs to restore and/or maintain sinus rhythm. The rational design of a new generation of AF-selective Na(+) channel blockers (NCBs) is emerging as a promising AF-suppressing strategy. Recent theoretical and experimental advances have generated insights into the mechanisms underlying AF maintenance and termination by antiarrhythmic drugs. Our understanding of antiarrhythmic drug-induced proarrhythmia has also grown in sophistication. These discoveries have created new possibilities in therapeutic targeting and renewed interest in improved NCB antiarrhythmic drugs. Recently described differences in atrial versus ventricular electrophysiology can be exploited in the prospective design of atrial-selective NCBs. Furthermore, state-dependent block has been shown to be an important modulator of NCB rate selectivity. Together, differential atrial-ventricular electrophysiological actions and state-dependent block form the backbone for the rational design of an AF-selective NCB. Synergistic combinations incorporating both NCB and block of K(+) currents may allow for further enhancement of AF selectivity. Future work on translating these basic research advances into the development of an optimized AF-selective NCB has the potential to provide safer and more effective pharmacotherapeutic options for AF, thereby fulfilling a major unmet clinical need. |
10,777 | Ventricular arrhythmia incidence in the rat is reduced by naloxone. | This study characterized the antiarrhythmic effects of the opioid receptor antagonist naloxone in rats subject to electrically induced and ischemic arrhythmias. Naloxone (2, 8 and 32 μmol/kg/min) was examined on heart rate, blood pressure, and the electrocardiogram (EKG) as well as for effectiveness against arrhythmias produced by occlusion of the left anterior descending coronary artery or electrical stimulation of the left ventricle. Naloxone reduced blood pressure at the highest dose tested while heart rate was dose-dependently reduced. Naloxone dose-dependently prolonged the P-R and QRS intervals and increased the RSh amplitude indicative of effects on cardiac sodium (Na) channels. Naloxone prolonged the Q-T interval suggesting a delay in repolarization. Naloxone effects were comparable to the comparator quinidine. Naloxone (32 μmol/kg/min) reduced ventricular fibrillation (VF) incidence to 38% (from 100% in controls). This same dose significantly increased the threshold for induction of ventricular fibrillation (VFt), prolonged the effective refractory period (ERP) and reduced the maximal following frequency (MFF). The patterns of ECG changes, reduction in ischemic arrhythmia (VF) incidence and changes in electrically induced arrhythmia parameters at high doses of naloxone suggest that it directly blocks cardiac Na and potassium (K) ion channels. |
10,778 | Long-term outcomes of catheter ablation of atrial fibrillation in dilated cardiomyopathy. | The long-term outcomes, efficacy and safety of catheter ablation in atrial fibrillation (AF) patients with dilated cardiomyopathy (DCM) have not been reported previously.</AbstractText>Forty nine patients with AF (59% longstanding persistent AF, LSP-AF) and DCM were enrolled. Circumferential pulmonary vein ablation (CPVA, paroxysmal AF), bidirectional block of lines and disappearance of complex fractionated atrial electrograms (CFAEs, persistent and LSP-AF) were the endpoints of the index and repeat procedures. Cumulative success rate reached 49% (mean, 1.4 procedures) during the first year, and dropped to 38% at median follow-up of 45 months (range, 36-64 months) for multiple procedures (mean, 1.9 ± 0.8 [1-4]). Incidence of procedural complications was similar to that of conventional procedures. In multivariate analysis, LSP-AF (OR, 7.40 [95% CI, 1.42-38.34]; P = 0.017) and larger left ventricular end-diastolic diameter (OR, 1.24 [95% CI, 1.01-1.52]; P = 0.034) were significant independent predictors of recurrent atrial tachyarrhythmia (ATa). Compared with patients with ATa recurrence, those free from ATa had better New York Heart Association functional class, 6-minute walk distance and left ventricular ejection fraction during long-term follow-up compared with pre-ablation, but this improvement was not sustained beyond 3 years.</AbstractText>In patients with DCM, current commonly used ablation strategies including CPVA, linear ablation and CFAE ablation are not associated with long-term AF treatment success up to five years. Freedom from ATa is associated with improved heart failure during but not beyond 3 years post ablation.</AbstractText>Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
10,779 | Rationale and design of a randomized, double-blind, event-driven, multicentre study comparing the efficacy and safety of oral rivaroxaban with placebo for reducing the risk of death, myocardial infarction or stroke in subjects with heart failure and significant coronary artery disease following an exacerbation of heart failure: the COMMANDER HF trial. | Thrombin is a critical element of crosstalk between pathways contributing to worsening of established heart failure (HF). The aim of this study is to explore the efficacy and safety of rivaroxaban 2.5 mg bid compared with placebo (with standard care) after an exacerbation of HF in patients with reduced ejection fraction (HF-rEF) and documented coronary artery disease.</AbstractText>This is an international prospective, multicentre, randomized, double-blind, placebo-controlled, event-driven study of approximately 5000 patients for a targeted 984 events. Patients must have a recent symptomatic exacerbation of HF, increased plasma concentrations of natriuretic peptides (B-type natriuretic peptide ≥200 pg/mL or N-terminal pro-B-type natriuretic peptide ≥800 pg/mL), with left ventricular ejection fraction ≤40% and coronary artery disease. Patients requiring anticoagulation for atrial fibrillation or other conditions will be excluded. After an index event (overnight hospitalization, emergency department or observation unit admission, or unscheduled outpatient parenteral treatment for worsening HF), patients will be randomized 1:1 to rivaroxaban or placebo (with standard of care). The primary efficacy outcome event is a composite of all-cause mortality, myocardial infarction or stroke. The principal safety outcome events are the composite of fatal bleeding or bleeding into a critical space with potential permanent disability, bleeding events requiring hospitalization and major bleeding events according to International Society on Thrombosis and Haemostasis bleeding criteria.</AbstractText>COMMANDER HF is the first prospective study of a target-specific oral antithrombotic agent in HF. It will provide important information regarding rivaroxaban use following an HF event in an HF-rEF patient population with coronary artery disease.</AbstractText>© 2015 The Authors. European Journal of Heart Failure published by John Wiley & Sons Ltd on behalf of European Society of Cardiology.</CopyrightInformation> |
10,780 | Quantitative tissue-tracking cardiac magnetic resonance (CMR) of left atrial deformation and the risk of stroke in patients with atrial fibrillation. | Recent evidence suggests that left atrial (LA) dysfunction may be mechanistically contributing to cerebrovascular events in patients with atrial fibrillation (AF). We investigated the association between regional LA function and a prior history of stroke during sinus rhythm in patients referred for catheter ablation of AF.</AbstractText>A total of 169 patients (59 ± 10 years, 74% male, 29% persistent AF) with a history of AF in sinus rhythm at the time of pre-ablation cardiac magnetic resonance (CMR) were analyzed. The LA volume, emptying fraction, strain (S), and strain rate (SR) were assessed by tissue-tracking cardiac magnetic resonance. The patients with a history of stroke or transient ischemic attack (n=18) had greater LA volumes (Vmax and Vmin; P=0.02 and P<0.001, respectively), lower LA total emptying fraction (P<0.001), lower LA maximum and pre-atrial contraction strains (Smax and SpreA; P<0.001 and P=0.01, respectively), and lower absolute values of LA SR during left ventricular (LV) systole and early diastole (SRs and SRe; P=0.005 and 0.03, respectively) than those without stroke/transient ischemic attack (n=151). Multivariable analysis demonstrated that the LA reservoir function, including total emptying fraction, Smax, and SRs, was associated with stroke/transient ischemic attack (odds ratio 0.94, 0.91, and 0.17; P=0.03, 0.02, and 0.04, respectively) after adjusting for the CHA2DS2-VASc score and LA Vmin.</AbstractText>Depressed LA reservoir function assessed by tissue-tracking cardiac magnetic resonance is significantly associated with a prior history of stroke/transient ischemic attack in patients with AF. Our findings suggest that assessment of LA reservoir function can improve the risk stratification of cerebrovascular events in AF patients.</AbstractText>© 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.</CopyrightInformation> |
10,781 | Reduction in Inappropriate ICD Therapy in MADIT-RIT Patients Without History of Atrial Tachyarrhythmia. | There are limited data whether history of atrial tachyarrhythmia (AT) modifies the risk of inappropriate ICD therapy, or the efficacy of novel ICD programming to reduce inappropriate ICD therapy events.</AbstractText>In MADIT-RIT, we investigated the effects of novel ICD programming with high-rate cut-off VT zone ≥ 200 bpm (arm B), or 60-second delayed therapy in the VT zone 170-199 bpm (arm C), compared to conventional programming VT zone>170 bpm (arm A) on first inappropriate ICD therapy in those with or those without AT prior to enrollment.</AbstractText>In patients with prior AT (n = 203, 14%) there was a higher risk of inappropriate ICD therapy (HR = 2.10, 95% CI: 1.38-3.20, P < 0.001), and inappropriate ICD shock (HR = 2.56, 95% CI: 1.38-4.74, P = 0.003) compared to those with no prior AT. The effects of innovative programming to reduce inappropriate ICD therapy with either high-rate cut-off or delayed VT therapy were similar in patients with prior AT (arm B vs. A HR = 0.11, P < 0.001, arm C vs. A HR = 0.17, P < 0.001), and also in patients without prior AT before enrollment (arm B vs. A HR = 0.15, P < 0.001, arm C vs. A HR = 0.24, P < 0.001, interaction P-values >0.10 for all).</AbstractText>Novel ICD programming with a high-rate cut-off or delayed therapy is equally beneficial to reduce inappropriate ICD therapy in patients with or without prior AT, despite the lower risk of inappropriate ICD therapy in patients without prior AT.</AbstractText>© 2015 Wiley Periodicals, Inc.</CopyrightInformation> |
10,782 | Gene therapy to treat cardiac arrhythmias. | Gene therapy to treat electrical dysfunction of the heart is an appealing strategy because of the limited therapeutic options available to manage the most-severe cardiac arrhythmias, such as ventricular tachycardia, ventricular fibrillation, and asystole. However, cardiac genetic manipulation is challenging, given the complex mechanisms underlying arrhythmias. Nevertheless, the growing understanding of the molecular basis of these diseases, and the development of sophisticated vectors and delivery strategies, are providing researchers with adequate means to target specific genes and pathways involved in disorders of heart rhythm. Data from preclinical studies have demonstrated that gene therapy can be successfully used to modify the arrhythmogenic substrate and prevent life-threatening arrhythmias. Therefore, gene therapy might plausibly become a treatment option for patients with difficult-to-manage acquired arrhythmias and for those with inherited arrhythmias. In this Review, we summarize the preclinical studies into gene therapy for acquired and inherited arrhythmias of the atria or ventricles. We also provide an overview of the technical advances in the design of constructs and viral vectors to increase the efficiency and safety of gene therapy and to improve selective delivery to target organs. |
10,783 | Late gadolinium enhancement of cardiac magnetic resonance imaging indicates abnormalities of time-domain T-wave alternans in hypertrophic cardiomyopathy with ventricular tachycardia. | The presence of myocardial scar detected by late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) imaging has been described as a good independent predictor of mortality in patients with hypertrophic cardiomyopathy (HCM). Time-domain T-wave alternans (TWA) is also a potential predictor of cardiac mortality in patients with left ventricular dysfunction.</AbstractText>The purpose of this study was to elucidate the relationship between LGE distribution and TWA in patients with HCM.</AbstractText>CMR and TWA analyses using Holter monitoring were performed in 42 patients with HCM. The average transmural extent of LGE was scored as 1-4 in each segment, and the sum of the LGE scores (total LGE score) was calculated for each patient. The correlation between the maximal time-domain TWA voltage and LGE findings was analyzed, and the differences in time-domain TWA voltage, total LGE score, and cardiac function assessed by CMR imaging in the presence or absence of ventricular tachycardia (VT) were also compared.</AbstractText>The total LGE score was significantly and positively correlated with the maximal time-domain TWA voltage (r = 0.59; P < .001). Furthermore, the total LGE score and maximal time-domain TWA voltage were significantly greater in patients who had episodes of VT (n = 21) than in those without VT (23 ± 7 vs. 10 ± 8; P < .001 and 87 ± 26 μV vs. 62 ± 12 μV; P < .001, respectively). However, the left ventricular ejection fraction did not statistically differ between patients with VT and those without VT (56% ± 14% vs. 61% ± 7%; P = .102).</AbstractText>The magnitude of the localized LGE was significantly correlated with abnormalities in ventricular repolarization as assessed by TWA and QT dispersion.</AbstractText>Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
10,784 | Use of Anticoagulants and Antiplatelet Agents in Stable Outpatients with Coronary Artery Disease and Atrial Fibrillation. International CLARIFY Registry. | Few data are available regarding the use of antithrombotic strategies in coronary artery disease patients with atrial fibrillation (AF) in everyday practice. We sought to describe the prevalence of AF and its antithrombotic management in a contemporary population of patients with stable coronary artery disease.</AbstractText>CLARIFY is an international, prospective, longitudinal registry of outpatients with stable coronary artery disease, defined as prior (≥12 months) myocardial infarction, revascularization procedure, coronary stenosis >50%, or chest pain associated with evidence of myocardial ischemia. Overall, 33,428 patients were screened, of whom 32,954 had data available for analysis at baseline; of these 2,229 (6.7%) had a history of AF. Median (interquartile range) CHA2DS2-VASc score was 4 (3, 5). Oral anticoagulation alone was used in 25.7%, antiplatelet therapy alone in 52.8% (single 41.8%, dual 11.0%), and both in 21.5%. OAC use was independently associated with permanent AF (p<0.001), CHA2DS2-VASc score (p=0.006), pacemaker (p<0.001), stroke (p=0.04), absence of angina (p=0.004), decreased left ventricular ejection fraction (p<0.001), increased waist circumference (p=0.005), and longer history of coronary artery disease (p=0.008). History of percutaneous coronary intervention (p=0.004) and no/partial reimbursement for cardiovascular medication (p=0.01, p<0.001, respectively) were associated with reduced oral anticoagulant use.</AbstractText>In this contemporary cohort of patients with stable coronary artery disease and AF, most of whom are theoretical candidates for anticoagulation, oral anticoagulants were used in only 47.2%. Half of the patients received antiplatelet therapy alone and one-fifth received both antiplatelets and oral anticoagulants. Efforts are needed to improve adherence to guidelines in these patients.</AbstractText>ISRCTN registry of clinical trials: ISRCTN43070564.</AbstractText> |
10,785 | Diltiazem vs. Metoprolol in the Management of Atrial Fibrillation or Flutter with Rapid Ventricular Rate in the Emergency Department. | Diltiazem (calcium channel blocker) and metoprolol (beta-blocker) are both commonly used to treat atrial fibrillation/flutter (AFF) in the emergency department (ED). However, there is considerable regional variability in emergency physician practice patterns and debate among physicians as to which agent is more effective. To date, only one small prospective, randomized trial has compared the effectiveness of diltiazem and metoprolol for rate control of AFF in the ED and concluded no difference in effectiveness between the two agents.</AbstractText>Our aim was to compare the effectiveness of diltiazem with metoprolol for rate control of AFF in the ED.</AbstractText>A convenience sample of adult patients presenting with rapid atrial fibrillation or flutter was randomly assigned to receive either diltiazem or metoprolol. The study team monitored each subject's systolic and diastolic blood pressures and heart rates for 30 min.</AbstractText>In the first 5 min, 50.0% of the diltiazem group and 10.7% of the metoprolol group reached the target heart rate (HR) of <100 beats per minute (bpm) (p < 0.005). By 30 min, 95.8% of the diltiazem group and 46.4% of the metoprolol group reached the target HR < 100 bpm (p < 0.0001). Mean decrease in HR for the diltiazem group was more rapid and substantial than that of the metoprolol group. From a safety perspective, there was no difference between the groups with respect to hypotension (systolic blood pressure < 90 mm Hg) and bradycardia (HR < 60 bpm).</AbstractText>Diltiazem was more effective in achieving rate control in ED patients with AFF and did so with no increased incidence of adverse effects.</AbstractText>Copyright © 2015 Elsevier Inc. All rights reserved.</CopyrightInformation> |
10,786 | Predictive value of programmed ventricular stimulation after catheter ablation of post-infarction ventricular tachycardia. | A recent meta-analysis demonstrated a survival benefit in post-infarction patients whose ventricular tachycardia (VT) was rendered noninducible by catheter ablation. Furthermore, patients with noninducible VT had a lower VT recurrence rate than did patients whose VT remained inducible after ablation.</AbstractText>The purpose of this multicenter cohort study was to assess whether noninducibility after VT ablation is independently associated with improved survival.</AbstractText>Data from 1,064 patients who underwent VT ablation for post-infarction VT at seven international centers were analyzed. The ablation procedure was considered successful if no VT was inducible at the end of the procedure and unsuccessful if VT remained inducible or if programmed stimulation was not performed at the end of the ablation.</AbstractText>Median follow-up time was 633 days. Noninducibility was independently associated with lower mortality (adjusted hazard ratio: 0.65; 95% confidence interval: 0.53 to 0.79; p<0.001). Atrial fibrillation, diabetes, and age were other independent predictors of higher mortality. Ablation of only the clinical VT in patients who also had inducible, nonclinical VTs was not associated with improved survival.</AbstractText>Noninducibility after VT ablation in patients with post-infarction VT is independently associated with lower mortality during long-term follow-up.</AbstractText>Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
10,787 | Dynamics of AV coupling during human atrial fibrillation: role of atrial rate. | The causal relationship between atrial and ventricular activities during human atrial fibrillation (AF) is poorly understood. This study analyzed the effects of an increase in atrial rate on the link between atrial and ventricular activities during AF. Atrial and ventricular time series were determined in 14 patients during the spontaneous acceleration of the atrial rhythm at AF onset. The dynamic relationship between atrial and ventricular activities was quantified in terms of atrioventricular (AV) coupling by AV synchrogram analysis. The technique identified n:m coupling patterns (n atrial beats in m ventricular cycles), quantifying their percentage, maximal length, and conduction ratio (= m/n). Simulations with a difference-equation AV model were performed to correlate the observed dynamics to specific atrial/nodal properties. The atrial rate increase significantly affected AV coupling and ventricular response during AF. The shortening of atrial intervals from 185 ± 32 to 165 ± 24 ms (P < 0.001) determined transitions toward AV patterns with progressively decreasing m/n ratios (from conduction ratio = 0.34 ± 0.09 to 0.29 ± 0.08, P < 0.01), lower occurrence (from percentage of coupled beats = 27.1 ± 8.0 to 21.8 ± 6.9%, P < 0.05), and higher instability (from maximal length = 3.9 ± 1.5 to 2.8 ± 0.7 s, P < 0.01). Advanced levels of AV block and coupling instability at higher atrial rates were associated with increased ventricular interval variability (from 123 ± 52 to 133 ± 55 ms, P < 0.05). AV pattern transitions and coupling instability in patients were predicted, assuming the filtering of high-rate irregular atrial beats by the slow recovery of nodal excitability. These results support the role of atrial rate in determining AV coupling and ventricular response and may have implications for rate control in AF. |
10,788 | Clinical characteristics, precipitating factors, management and outcome of patients with prior stroke hospitalised with heart failure: an observational report from the Middle East. | The purpose of this study is to report the prevalence, clinical characteristics, precipitating factors, management and outcome of patients with prior stroke hospitalised with acute heart failure (HF).</AbstractText>Retrospective analysis of prospectively collected data.</AbstractText>Data were derived from Gulf CARE (Gulf aCute heArt failuRe rEgistry), a prospective multicentre study of consecutive patients hospitalised with acute HF in 2012 in seven Middle Eastern countries and analysed according to the presence or absence of prior stroke; demographics, management and outcomes were compared.</AbstractText>A total of 5005 patients with HF.</AbstractText>In-hospital and 1-year outcome.</AbstractText>The prevalence of prior stroke in patients with HF was 8.1%. Patients with stroke with HF were more likely to be admitted under the care of internists rather than cardiologists. When compared with patients without stroke, patients with stroke were more likely to be older and to have diabetes mellitus, hypertension, atrial fibrillation, hyperlipidaemia, chronic kidney disease, ischaemic heart disease, peripheral arterial disease and left ventricular dysfunction (p=0.001 for all). Patients with stroke were less likely to be smokers (0.003). There were no significant differences in terms of precipitating risk factors for HF hospitalisation between the two groups. Patients with stroke with HF had a longer hospital stay (mean±SD days; 11±14 vs 9±13, p=0.03), higher risk of recurrent strokes and 1-year mortality rates (32.7% vs 23.2%, p=0.001). Multivariate logistic regression analysis showed that stroke is an independent predictor of in-hospital and 1-year mortality.</AbstractText>This observational study reports high prevalence of prior stroke in patients hospitalised with HF. Internists rather than cardiologists were the predominant caregivers in this high-risk group. Patients with stroke had higher risk of in-hospital recurrent strokes and long-term mortality rates.</AbstractText>NCT01467973.</AbstractText>Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.</CopyrightInformation> |
10,789 | Patient selection in heart failure with preserved ejection fraction clinical trials. | Recent clinical trials in patients with heart failure with preserved ejection fraction (HFpEF) have provided important insights into participant selection strategies. Historically, HFpEF trials have included patients with relatively preserved left ventricular ejection fraction ranging from 40% to 55% and a clinical history of heart failure. Contemporary HFpEF trials have also incorporated inclusion criteria such as hospitalization for HFpEF, altered functional capacity, cardiac structural and functional abnormalities, and abnormalities in neurohormonal status (e.g., elevated natriuretic peptide levels). Careful analyses of the effect of these patient selection criteria on outcomes in prior trials provide valuable lessons for future trial design. We review recent and ongoing HFpEF clinical trials from a patient selection perspective and appraise trial patient selection methodologies in relation to outcomes. This review reflects discussions between clinicians, scientists, trialists, regulators, and regulatory representatives at the 10th Global CardioVascular Clinical Trialists Forum in Paris, France, on December 6, 2013. |
10,790 | Safety and Efficacy of the Totally Subcutaneous Implantable Defibrillator: 2-Year Results From a Pooled Analysis of the IDE Study and EFFORTLESS Registry. | The entirely subcutaneous implantable cardioverter-defibrillator (S-ICD) is the first implantable defibrillator that avoids placing electrodes in or around the heart. Two large prospective studies (IDE [S-ICD System IDE Clinical Investigation] and EFFORTLESS [Boston Scientific Post Market S-ICD Registry]) have reported 6-month to 1-year data on the S-ICD.</AbstractText>The objective of this study was to evaluate the safety and efficacy of the S-ICD in a large diverse population.</AbstractText>Data from the IDE and EFFORTLESS studies were pooled. Shocks were independently adjudicated, and complications were measured with a standardized classification scheme. Enrollment date quartiles were used to assess event rates over time.</AbstractText>Eight hundred eighty-two patients who underwent implantation were followed for 651±345 days. Spontaneous ventricular tachyarrhythmia (VT)/ventricular fibrillation (VF) events (n=111) were treated in 59 patients; 100 (90.1%) events were terminated with 1 shock, and 109 events (98.2%) were terminated within the 5 available shocks. The estimated 3-year inappropriate shock rate was 13.1%. Estimated 3-year, all-cause mortality was 4.7% (95% confidence interval: 0.9% to 8.5%), with 26 deaths (2.9%). Device-related complications occurred in 11.1% of patients at 3 years. There were no electrode failures, and no S-ICD-related endocarditis or bacteremia occurred. Three devices (0.3%) were replaced for right ventricular pacing. The 6-month complication rate decreased by quartile of enrollment (Q1: 8.9%; Q4: 5.5%), and there was a trend toward a reduction in inappropriate shocks (Q1: 6.9% Q4: 4.5%).</AbstractText>The S-ICD demonstrated high efficacy for VT/VF. Complications and inappropriate shock rates were reduced consistently with strategic programming and as operator experience increased. These data provide further evidence for the safety and efficacy of the S-ICD. (Boston Scientific Post Market S-ICD Registry [EFFORTLESS]; NCT01085435; S-ICD® System IDE Clinical Study; NCT01064076).</AbstractText>Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
10,791 | Brugada syndrome: clinical and genetic findings. | Brugada syndrome is a rare, inherited cardiac disease leading to ventricular fibrillation and sudden cardiac death in structurally normal hearts. Clinical diagnosis requires a Brugada type I electrocardiographic pattern in combination with other clinical features. The most effective approach to unmasking this diagnostic pattern is the use of ajmaline and flecainide tests, and the most effective intervention to reducing the risk of death is the implantation of a cardioverter defibrillator. To date, 18 genes have been associated with the disease, with the voltage-gated sodium channel α type V gene (SCN5A) being the most common one to date. However, only 30-35% of diagnosed cases are attributable to pathogenic variants in known genes, emphasizing the need for further genetic studies. Despite recent advances in clinical diagnoses and genetic testing, risk stratification and clinical management of patients with Brugada syndrome remain challenging.Genet Med 18 1, 3-12. |
10,792 | The relationship between tricuspid regurgitation severity and right atrial mechanics: a speckle tracking echocardiography study. | The aim at this study was to assess the influence of the tricuspid regurgitation volume (TRvol) in right atrium (RA) reservoir phase myocardial mechanics. We included 55 heart failure (HF) patients referred for transthoracic echocardiography during a 2-month period. 18 Had HF with a reduced ejection fraction (HFREF) and 37 HF with a preserved ejection fraction (HFPEF). TR was chronic and functional. TRvol was calculated according to the PISA method. This study of RA used 2D-speckle tracking echocardiography to measure strain (rεR) and strain rate (rSR(R)). The reference frame coincided with the onset of the QRS. RA stiffness was assessed as the ratio: (rE/e')/rε(R). The median age of the sample was 78 (64-84) years, with female gender predominance (63.6%). The median value of rε(R) was 16% (range, 12.7-24.0) and of rSR(R) was 1.57 s(-1) (range, 1.09-2.05). We observed a significant negative correlation between rε(R) (r = -0.68, p < 0.01) and rSR(R) (r = -0.58, p < 0.01) and TRvol. RA mechanics decreased significantly with an increase in the TR grade. We created two multivariate linear regression models for rε(R) and rSR(R), separately for the patients with sinus rhythm or atrial fibrillation. The TRvol was independently associated with rε(R) after adjusting to the RA area, right ventricular longitudinal systolic function and the estimated pulmonary vascular resistance. We demonstrated an increase in RA stiffness with an increase in TR severity, and an association for functional status (NYHA class) and RA compliance. The HFREF group had a significantly lower rε(R) and rSR(R) that the HFPEF patients. According to our study, in HF patients, a chronic volume overload state significantly reduced the RA reservoir phase mechanics. |
10,793 | Comparison of the efficiency of Na+/Ca2+ exchanger or Na+/H+ exchanger inhibition and their combination in reducing coronary reperfusion-induced arrhythmias. | During ischaemia/reperfusion, the rise in [Na(+)](i), induced by simultaneous depression of the Na(+)/K(+)-ATPase and activation of the Na(+)/H(+) exchanger (NHE), shifts the Na(+)/Ca(2+) exchanger (NCX) into reverse transport mode, resulting in Ca(2+)(i)overload, which is a critical factor in enhancing the liability to cardiac arrhythmias. The inhibition of NHE, and recently NCX has been suggested to effectively protect the heart from reperfusion-induced arrhythmias. In this study, we investigated and compared the efficacy of individual or the simultaneous inhibition of the NHE and NCX against reperfusion-induced arrhythmias in Langendorff-perfused rat hearts by applying a commonly used regional ischaemia-reperfusion protocol. The NHE and NCX were inhibited by cariporide and SEA0400 or the novel, more selective ORM-10103, respectively. Arrhythmia diagrams calculated for the reperfusion period were analysed for the incidence and duration of extrasystoles (ESs), ventricular tachycardia (VT) and ventricular fibrillation (VF). NHE inhibition by cariporide was highly efficient in reducing the recorded reperfusion-induced arrhythmias. Following the application of SEA0400 or ORM-10103, the number and duration of arrhythmic periods were efficiently or moderately decreased. While both NCX inhibitors effectively reduced ESs, the most frequently triggered arrhythmias, they exerted limited or no effect on VTs and VFs. Of the NCX inhibitors, ORM-10103 was more effective. Surprisingly, the simultaneous inhibition of the NCX and NHE failed to significantly improve the antiarrhythmic efficacy reached by NCX blockade alone. In conclusion, although principal simultaneous NHE+NCX inhibition should be highly effective against all types of the recorded reperfusion-induced arrhythmias, NCX inhibitors, alone or in combination with cariporide, seem to be moderately suitable to provide satisfactory cardioprotection - at least in the present arrhythmia model. Since ORM-10103 and SEA0400 are known to effectively inhibit after-depolarisations, it is suggested that their efficacy and that of other NCX inhibitors may be higher and more pronounced in the predominantly Ca(2+)(i)-dependent triggered arrhythmias. |
10,794 | Validation of a simple risk stratification tool for patients implanted with Cardiac Resynchronization Therapy: the VALID-CRT risk score. | Mortality after cardiac resynchronization therapy (CRT) is difficult to predict. We sought to design and validate a simple prognostic score for patients implanted with CRT, based on readily available clinical variables, including age, gender, left ventricular ejection fraction (LVEF), New York Heart Association (NYHA) class, presence/absence of atrial fibrillation, presence/absence of atrioventricular junction ablation, coronary heart disease, diabetes, and implantation of a CRT device with defibrillation.</AbstractText>For predictive modelling, 5153 consecutive patients enrolled in 72 European centres (79% male; LVEF 25.9 ± 6.85%; NYHA class III-IV 77.5%; QRS 158.4 ± 32.3 ms) were randomly split into derivation (70%) and validation (30%) samples. The primary endpoint was total mortality and the secondary endpoint was cardiovascular mortality. The final predictive model fit was assessed by plotting observed vs. predicted survival.</AbstractText>In the entire cohort, 1004 deaths occurred over a follow-up of 14 409 person years. Total mortality ranged from 3.1% to 28.2% at 2 years in the first and fifth quintile of the risk score, respectively. At 5 years, total mortality was 10.3%, 18.6%, 27.6%, 36.1%, and 58.8%, from the first to the fifth quintile. Compared with the lowest quintile (Q), total mortality was significantly higher in the other four quintiles [Q2 hazard ratio (HR) = 1.71; Q3 HR = 2.20; Q4 HR = 4.03; Q5 HR = 8.03; all P < 0.001). The final model, which was based on the entire cohort using the above variables, showed a good discrimination (Harrell's c = 0.70) and high explained variation (0.26). The mean predicted survival fitted well with the observed survival for up to 6 years of follow-up.</AbstractText>The VALID-CRT risk score, which is based on routine, readily available clinical variables, reliably predicted the long-term total and cardiovascular mortality in patients undergoing CRT. While this score cannot be used to predict the benefit of CRT, it may be useful for predicting survival after CRT. This may have useful implications for follow-up.</AbstractText>© 2015 The Authors. European Journal of Heart Failure © 2015 European Society of Cardiology.</CopyrightInformation> |
10,795 | Intraarrest rhythms and rhythm conversion in asphyxial cardiac arrest. | The objective was to analyze the cardiac arrest rhythms presenting during asphyxial cardiac arrest (ACA).</AbstractText>Asphyxial cardiac arrest was induced in 30 Landrace large white piglets, aged 12 to 15 weeks and with a mean (±SD) weight of 20 (±2) kg. After the onset of cardiac arrest, the animals were left untreated for 4 minutes, after which cardiopulmonary resuscitation was commenced. Heart rhythms were monitored from the onset of asphyxia until return of spontaneous circulation or death.</AbstractText>After endotracheal tube clamping and prior to cardiac arrest, normal sinus rhythm was noted in 14 animals, atrial fibrillation in two animals, Mobitz II atrioventricular block in 10 animals, and third-degree atrioventricular block in four animals. At the onset of cardiac arrest, seven animals had ventricular fibrillation (VF), two had asystole, and 21 had pulseless electrical activity (PEA). During the 4-minute period of untreated arrest, however, significant changes in the monitored rhythm were noted; at the end of the fourth minute, 19 animals had VF, two animals had asystole, and nine animals had PEA.</AbstractText>The most common rhythm after 4 minutes of untreated ACA was VF, while in 57% of animals, PEA was spontaneously converted to VF during the cardiac arrest interval.</AbstractText>© 2015 by the Society for Academic Emergency Medicine.</CopyrightInformation> |
10,796 | Variations of heart rate variability parameters prior to the onset of ventricular tachyarrhythmia and sinus tachycardia in ICD patients. Results from the heart rate variability analysis with automated ICDs (HAWAI) registry. | The HAWAI registry evaluated the role of heart rate variability in predicting the occurrence of ventricular tachycardia and fibrillation (VT/VF) and sinus tachycardia in patients with an implantable cardioverter-defibrillator (45 patients with 155 RR recordings). A significant decrease of the mean value of all RR intervals (MeanNN) was observed in the period starting 20 and 40 min prior to VT/VF and sinus tachycardia, respectively. The standard deviation of RR intervals (SDNN) and the power at low frequency (LF) were the only parameters with significant changes prior to VT/VF. For sinus tachycardia, the root mean square of successive differences of all successive RR intervals (r-MSSD) and the power at low and high frequency (HF) decreased, whereas SDNN and the power at very low frequency increased. Comparison of RR recordings preceding VT/VF and sinus tachycardia revealed significant differences of the MeanNN, SDNN, r-MSSD, LF and HF. Based on a classification and regression tree analysis, MeanNN, SDNN and r-MSSD showed a sensitivity of 94.4% and a specificity of 50.6% as predictors of VT/VF. Our results suggest that the temporal changes in heart rate before an arrhythmic event can be used to predict the occurrence of VT/VF. These parameters may be used to optimize pacing therapies designed to prevent VT/VF recurrences as well as for improving device-based discriminators for VT/VF and sinus tachycardia. |
10,797 | The relationship of QRS morphology with cardiac structure and function in patients with heart failure. | The relationship of QRS morphology with cardiac structure and function in patients with heart failure is uncertain.</AbstractText>Patients with a clinical diagnosis of heart failure and objective evidence of cardiac dysfunction [either a left ventricular ejection fraction (LVEF) <50 % or an amino-terminal pro-brain natriuretic peptide (NT-proBNP) ≥400 pg/ml] who had been investigated by cardiac magnetic resonance imaging (CMRI) were identified. QRS duration ≥120 ms was grouped morphologically as left (LBBB), right bundle branch block (RBBB) or indeterminate.</AbstractText>Of 877 patients, 320 (36 %) had QRS ≥ 120 ms. Compared to patients with LBBB, those with RBBB had a lower median [inter-quartile range (IQR)] right ventricular (RV) ejection fraction [RBBB: 46 (37-57); LBBB: 52 (42-61) %; p = 0.014], greater median (IQR) RV mass [RBBB: 53 (42-73); LBBB: 45 (36-56) g; p < 0.001], higher median (IQR) plasma NT-proBNP [RBBB: 2013 (659-3573); LBBB: 1159 (589-2207) pg/ml, p = 0.026], more signs of peripheral congestion and higher prevalence of atrial fibrillation but had similar LVEF. During a median follow-up of 1302 days (IQR: 742-2237), 311 patients died. Compared with patients who had QRS < 120 ms, those with RBBB [HR 1.98, 95 % CI (1.37-2.86); p < 0.001] had a higher mortality. Age and NT-proBNP were the strongest independent predictors of mortality; neither QRS nor CMRI variables improved prediction.</AbstractText>In patients with heart failure and QRS ≥ 120 ms, RBBB is associated with more severe RV dysfunction and congestion and a worse prognosis. However, neither QRS morphology nor CMRI data provide independent prognostic information in a multivariable analysis including NT-proBNP.</AbstractText> |
10,798 | Effects of antiarrhythmic peptide 10 on acute ventricular arrhythmia. | To observe the effects antiarrhythmic peptide 10 (AAP10) aon acute ventricular arrhythmia and the phosphorylation state of ischemic myocardium connexin.</AbstractText>Acute total ischemia and partial ischemia models were established by ceasing perfusion and ligating the left anterior descending coronary artery in SD rats. The effects of AAP10 (1 mg/L) on the incidence rate of ischemia-induced ventricular arrhythmia were observed. The ischemic myocardium was sampled to detect total-Cx43 and NP-Cx43 by immunofluorescent staining and western blotting. the total-Cx43 expression was detected through image analysis system by semi-quantitative analysis.</AbstractText>AAP10 could significantly decrease the incidence of ischemia-induced ventricular tachycardia and ventricular fibrillation. During ischemic stage, total ischemia (TI) and AAP10 total ischemia (ATI) groups were compared with partial ischemia (PI) and AAP10 partial ischemia (API) groups. The rates of incidence for arrhythmia in the ATI and API groups (10% and 0%) were lower than those in the TI and PI groups (60% and 45%). The difference between the two groups was statistically significant (P=0.019, P=0.020). The semi-quantitative analysis results of the ischemic myocardium showed that the total-Cx43 protein expression distribution areas for TI, ATI, PI and API groups were significantly decreased compared with the control group. On the other hand, the NP-Cx43 distribution areas of TI, ATI, PI and API groups were significantly increased compared with the control group (P>0.05). AAP10 could increase the total-Cx43 expression in the ischemic area and decrease the NP-Cx43 expression. Western blot results were consistent with the results of immunofluorescence staining.</AbstractText>AAP10 can significantly decrease the rate of incidence of acute ischemia-induced ventricular tachycardia and ventricular fibrillation. Acute ischemic ventricular arrhythmias may have a relationship with the decreased phosphorylation of Cx43 induced by ischemia. AAP10 may stimulate the phosphorylation of Cx43 by increasing the total-Cx43 expression and decreasing the NP-Cx43 expression in the ischemic area, so as to decrease ventricular arrhythmia.</AbstractText>Copyright © 2015 Hainan Medical College. Production and hosting by Elsevier B.V. All rights reserved.</CopyrightInformation> |
10,799 | The effects of serotonin on the electrophysiological properties of atrioventricular node during an experimental atrial fibrillation. | A few studies explored the atrioventricular (AV) nodal effects of 5-hydroxytyptamine (serotonin, 5-HT) during supraventricular tachyarrhythmia. The aims of the present study are to investigate (i) 5-HT effects on the rate-dependent electrophysiological functions of AV node during atrial fibrillation (AF) and (ii) the potential contribution of various 5-HT receptors and the role of the autonomic nervous system on 5-HT effects on AV nodal properties. The specific stimulation protocols were applied to detect the electrophysiological parameters of AV node in seven groups of isolated rabbit AV nodal preparations (N = 75) in the presence of 5-HT (0.5, 1, 5, 10, and 20 μM) and its receptor antagonists, nadolol and atropine. The simulated AF protocol was executed in a separate group, and specific indices, including mean His-His interval, a zone of concealment (ZOC), and concealed beats recorded. 5-HT (10-20 μM) increased significantly functional refractory period, Wenckebach cycle length, and excitability index (p < 0.05). The percentage of gap and echo beats was significantly decreased with increasing 5-HT concentrations (p < 0.05). Ketanserin and tropisetron increased significantly atrial-His conduction time, effective refractory period, and Wenckebach cycle length (p < 0.05). 5-HT effects on functional refractory period and Wenckebach cycle length were abrogated by tropisetron and nadolol (p < 0.05). 5-HT elicited prolongation of ZOC and nodal refractoriness (p < 0.05). We conclude that 5-HT elicited prolongation of the nodal refractoriness more than atrial-His conduction time leads to increase in the excitability index and ZOC without significant reduction of the ventricular rates during AF. |
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