Usefulness of electrophysiologic study to determine the clinical tolerance of arrhythmia recurrences during amiodarone therapy

The relation of clinical and electrophysiologic variables to outcome was evaluated in 121 patients treated with amiodarone for sustained ventricular tachyarrhythmias. Electrophysiologic study was performed in all patients a mean of 14 days after beginning amiodarone therapy. Forty-six patients who were given oral amiodarone therapy experienced arrhythmia recurrence. Multivariate analysis was performed using 16 clinical and electrophysiologic variables to determine which factors were associated with 1) arrhythmia recurrence and 2) a poorly tolerated arrhythmia recurrence (that is, cardiac arrest or sudden cardiac death) during oral amiodarone therapy. No variable predicted arrhythmia recurrence. Five variables correlated significantly with a poorly tolerated arrhythmia recurrence. Hemodynamic stability of the arrhythmia induced on electrophysiologic testing during amiodarone therapy had the best predictive value (p < 0.001). Younger age, lower ejection fraction, a poorly tolerated rhythm at clinical presentation and absence of left ventricular aneurysm were also associated with a poorly tolerated arrhythmia recurrence.Only 3 of 57 patients who had a well tolerated arrhythmia induced on electrophysiologic testing during amiodarone therapy had recurrence of a poorly tolerated arrhythmia versus 19 of 47 who had hemodynamically unstable arrhythmias induced during amiodarone therapy (p < 0.001). Thus, electrophysiologic testing during amiodarone therapy appears useful in identifying patients who are prone to have catastrophic arrhythmia recurrences and could allow for the institution of additional or alternative modes of therapy

Influence of Gender on Arrhythmia Characteristics and Outcome in the Multicenter UnSustained Tachycardia Trial

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73630/1/j.1540-8167.2004.04050.x.pd

Utilization Rates of Implantable Cardioverter-Defibrillators for Primary Prevention of Sudden Cardiac Death: A 2012 Calculation for a Midwestern Health Referral Region

Background Utilization rates (URs) for implantable cardioverter-defibrillators (ICDs) for primary prevention of sudden cardiac death (PPSCD) are lacking in the community. Objective To establish the ICD UR in central Indiana. Methods A query run on two hospitals in a health information exchange database in Indianapolis identified patients between 2011 and 2012 with left ventricular ejection fraction (EF) ≤0.35. ICD-eligibility and utilization were determined from chart review. Results We identified 1,863 patients with at least one low-EF study. Two cohorts were analyzed: 1,672 patients without, and 191 patients with, ICD-9-CM procedure code 37.94 for ICD placement. We manually reviewed a stratified (by hospital) random sample of 300 patients from the no-ICD procedure code cohort and found that 48 (16%) had no ICD but had class I indications for ICD. Eight of 300 (2.7%) actually had ICD implantation for PPSCD. Review of all 191 patients in the ICD procedure code cohort identified 70 with ICD implantation for PPSCD. The ICD UR (ratio between patients with ICD for PPSCD and all with indication) was 38% overall (95% CI 28–49%). URs were 48% for males (95% CI 34–61%), 21% for females (95% CI 16–26%, p=0.0002 vs males), 40% for whites (95% CI 27–53%), and 37% for blacks (95% CI 28–46%, p=0.66 vs whites). Conclusions The ICD UR is 38% among patients meeting Class I indications, suggesting further opportunities to improve guideline compliance. Furthermore, this study illustrates limitations in calculating ICD UR using large electronic repositories without hands-on chart review

Treatment of Obstructive Sleep Apnea Reduces the Risk of Atrial Fibrillation Recurrence After Catheter Ablation

ObjectivesThe aim of this study was to examine the effect of continuous positive airway pressure (CPAP) therapy on atrial fibrillation (AF) recurrence in patients with obstructive sleep apnea (OSA) undergoing pulmonary vein isolation (PVI).BackgroundOSA is a predictor of AF recurrence following PVI. However, the impact of CPAP therapy on PVI outcome in patients with OSA is poorly known.MethodsAmong 426 patients who underwent PVI between 2007 and 2010, 62 patients had a polysomnography-confirmed diagnosis of OSA. While 32 patients were “CPAP users” the remaining 30 patients were “CPAP nonusers.” The recurrence of any atrial tachyarrhythmia, use of antiarrhythmic drugs, and need for repeat ablations were compared between the groups during a follow-up period of 12 months. Additionally, the outcome of patients with OSA was compared to a group of patients from the same PVI cohort without OSA.ResultsCPAP therapy resulted in higher AF-free survival rate (71.9% vs. 36.7%; p = 0.01) and AF-free survival off antiarrhythmic drugs or repeat ablation following PVI (65.6% vs. 33.3%; p = 0.02). AF recurrence rate of CPAP-treated patients was similar to a group of patients without OSA (HR: 0.7, p = 0.46). AF recurrence following PVI in CPAP nonuser patients was significantly higher (HR: 2.4, p < 0.02) and similar to that of OSA patients managed medically without ablation (HR: 2.1, p = 0.68).ConclusionsCPAP is an important therapy in OSA patients undergoing PVI that improves arrhythmia free survival. PVI offers limited value to OSA patients not treated with CPAP

Scar heterogeneity on cardiovascular magnetic resonance as a predictor of appropriate implantable cardioverter defibrillator therapy

Background: Despite the survival benefit of implantable-cardioverter-defibrillators (ICDs), the vast majority of patients receiving an ICD for primary prevention do not receive ICD therapy. We sought to assess the role of heterogeneous scar area (HSA) identified by late gadolinium enhancement cardiovascular magnetic resonance (LGE-CMR) in predicting appropriate ICD therapy for primary prevention of sudden cardiac death (SCD). Methods: From September 2003 to March 2011, all patients who underwent primary prevention ICD implantation and had a pre-implantation LGE-CMR were identified. Scar size was determined using thresholds of 4 and 6 standard deviations (SD) above remote normal myocardium; HSA was defined using 3 different criteria; as the region between 2 SD and 4 SD (HSA2-4SD), between 2SD and 6SD (HSA2-6SD), and between 4SD and 6SD (HSA4-6SD). The end-point was appropriate ICD therapy. Results: Out of 40 total patients followed for 25 ± 24 months, 7 had appropriate ICD therapy. Scar size measured by different thresholds was similar in ICD therapy and non-ICD therapy groups (P = NS for all). However, HSA2-4SD and HSA4-6SD were significantly larger in the ICD therapy group (P = 0.001 and P = 0.03, respectively). In multivariable model HSA2-4SD was the only significant independent predictor of ICD therapy (HR = 1.08, 95%CI: 1.00-1.16, P = 0.04). Kaplan-Meier analysis showed that patients with greater HSA2-4SD had a lower survival free of appropriate ICD therapy (P = 0.026). Conclusions: In primary prevention ICD implantation, LGE-CMR HSA identifies patients with appropriate ICD therapy. If confirmed in larger series, HSA can be used for risk stratification in primary prevention of SCD

ACC/AHA/ESC 2006 guidelines for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death: A report of the American College of Cardiology/American Heart Association Task Force and the European Society of Cardiology Committee for Practice Guidelines

Several excellent guidelines already exist on treating patients who have ventricular arrhythmias (Table 1). The purpose of this document is to update and combine the previously published recommendations into one source approved by the major cardiology organizations in the United States and Europe. We have consciously attempted to create a streamlined document, not a textbook, that would be useful specifically to locate recommendations on the evaluation and treatment of patients who have or may be at risk for ventricular arrhythmias. Thus, sections on epidemiology, mechanisms and substrates, and clinical presentations are brief, because there are no recommendations for those sections. For the other sections, the wording has been kept to a minimum, and clinical presentations have been confined to those aspects relevant to forming recommendations

ACC/AHA/ESC 2006 Guidelines for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death. A Report of the American College of Cardiology/American Heart Association Task Force and the European Society of Cardiology Committee for Practice Guidelines.

Several excellent guidelines already exist on treating patients who have ventricular arrhythmias (Table 1).The purpose of this document is to update and combine the previously published recommendations into one source approved by the major cardiology organizations in the United States and Europe. We have consciously attempted to create a streamlined document, not a textbook, that would be useful specifically to locate recommendations on the evaluation and treatment of patients who have or may be at risk for ventricular arrhythmias. Thus, sections on epidemiology, mechanisms and substrates, and clinical presentations are brief, because there are no recommendations for those sections. For the other sections, the wording has been kept to a minimum, and clinical presentations have been confined to those aspects relevant to forming recommendations

European Heart Rhythm Association (EHRA)/Heart Rhythm Society (HRS)/Asia Pacific Heart Rhythm Society (APHRS)/Latin American Heart Rhythm Society (LAHRS) expert consensus on risk assessment in cardiac arrhythmias: use the right tool for the right outcome, in the right population.

In clinical practice and for scientific purposes, cardiologists and primary care physicians perform risk assessment in patients with cardiac diseases or conditions with high risk of developing such. The European Heart Rhythm Association (EHRA), Heart Rhythm Society (HRS), Asia Pacific Heart Rhythm Society (APHRS), and the Latin American Heart Rhythm Society (LAHRS) set down this expert consensus statement task force to summarize the consensus regarding risk assessment in cardiac arrhythmias. Objectives were to raise awareness of using the right risk assessment tool for a given outcome in a given population, and to provide physicians with practical proposals that may lead to rational and evidence-based risk assessment and improvement of patient care in this regard. A large variety of methods are used for risk assessment and choosing the best methods and tools hereof in a given situation is not simple. Even though parameters and test results found associated with increased risk of one outcome (e.g. death) may also be associated with higher risk of other adverse outcomes, specific risk assessment strategies should be used only for the purposes for which they are validated. The work of this task force is summarized in a row of consensus statement tables