Swain, William H.

AbstractIntroductionLittle is known regarding the prevalence and prognostic implications of non‐sustained ventricular tachycardia (NSVT) in patients with wild‐type transthyretin cardiac amyloidosis (ATTRwt‐CA). We aimed to investigate the prevalence of NSVT in patients with ATTRwr‐CA, and the association of NSVT with sustained ventricular arrhythmias (VA) and all‐cause mortality.MethodsIn a cohort of ATTRwt‐CA patients from 2011 to 2022 without prior sustained VA, we ascertained the presence and characteristics of NSVT during clinically indicated ambulatory Holter monitoring. Patients were stratified based on the presence of NSVT at baseline. The primary and secondary endpoints of sustained VA and all‐cause mortality, respectively, were assessed during follow‐up.ResultsThe cohort included 217 patients with ATTRwt‐CA (95% males, median age 75 years; median NYHA class 2). Baseline Holter monitoring demonstrated NSVT in 116 (53%) patients. During a median follow‐up of 27 months (IQR 16–45) after the index Holter monitor, 11 (5.1%) patients reached the primary endpoint of sustained VA (incidence 1.8 per 100 person‐years, all monomorphic VT), and 46 (21%) patients died. In univariable Cox proportional hazard model, NYHA class 3 or 4 heart failure (p = .048), the presence of NSVT (p = .04), the duration of longest NSVT run (p = .029), and the percentage of ventricular ectopy (p < .001) were associated with the primary outcome. When adjusting for age and NYHA class 3 or 4 heart failure, the presence of NSVT remained associated with the primary outcome (p = .03). All‐cause mortality was not significantly different between patients with and without NSVT. A cutoff for ventricular ectopy burden of 0.5%, the median for all patients in this study, was associated with increased risk in sustained VA (log‐rank p = .004) and mortality (log‐rank p = .02).ConclusionNSVT is highly prevalent among ATTRwt‐CA patients undergoing clinically indicated Holter monitoring and may confer an increased risk of incident sustained VA.

Introduction: Advanced imaging with cardiac magnetic resonance (CMR) or computed tomography (CCT) can be helpful for planning of ventricular tachycardia (VT) ablation procedures by defining the arrhythmogenic substrate. The frequency with which these modalities are utilized in the pre-ablation setting and the associated outcomes remain poorly studied. Objectives: (1) Determine the utilization of advanced cardiac imaging prior to structural VT ablation; (2) establish factors associated with improved VT ablation outcomes Methods: We retrospectively evaluated all VT ablations performed in patients with structural heart disease at a tertiary referral institution during a 2.5 year period (1/2020 - 7/2022). We documented pre-ablation use of cardiac imaging modalities and investigated their association with acute and long-term ablation outcomes. The primary outcome was time to VT recurrence, cardiac transplant, or death. Results: Our dataset included n = 129 subjects. Median post-ablation follow-up was 17 months. Recent echocardiogram, CMR, or CCT (<3 months pre-ablation) had been performed in 113 (88%), 48 (37%), and 31 (24%) patients, respectively. CMR was not associated with procedural success, post-ablation VT recurrence (p = 1), or the composite primary outcome (p = 0.72). Similarly, recent CCT was not associated with procedural success (p = 0.5), VT recurrence (p = 0.3), or the composite primary outcome (p = 0.31). When adjusted for other variables, EF (p = 0.048), recent echo (p = 0.02), and procedural success (p = 0.013) were associated with the primary outcome, but recent CCT (p = 0.11) and CMR (p = 0.4) were not. These results did not differ significantly in patients with ischemic and non-ischemic cardiomyopathy. Conclusions: In this large tertiary care ablation center, CMR and CCT were utilized in only a fraction of patients prior to VT ablations. In multivariate analysis, CMR or CCT were not associated with improved acute or long-term ablation outcomes.