No abstract

AimsData on outcomes in patients using the wearable cardioverter-defibrillator (WCD) > 90 days are limited. We aimed to analyse the clinical course of patients with WCD use ≤90 days vs. WCD use >90 days.Methods and resultsWe assessed arrhythmia events during WCD use, and ejection fraction (EF) improvement/implantable cardioverter-defibrillator (ICD) implantation at the end of WCD use in patients with WCD use ≤90 days vs. WCD use >90 days enrolled in the WEARIT-II registry, further assessed by disease aetiology (ischaemic vs. non-ischaemic vs. congenital/inherited heart disease). There were 981 (49%) patients with WCD use >90 days, and 1019 patients with WCD use ≤90 days (median 120 vs. 55 days). There was a lower incidence of sustained ventricular tachycardia/ventricular fibrillation (VT/VF) events (11 vs. 50 events per 100 patient-years, P < 0.001), WCD treated VT/VF events (1 vs. 8 events per 100 patient-years, P < 0.001), and non-sustained VT events (21 vs. 51 events per 100 patient-years, P = 0.008) with WCD use >90 vs. WCD use ≤90 days. Non-ischaemic cardiomyopathy patients presented with similar rates of sustained VT/VF events during WCD use >90 vs. ≤90 days (13.4 vs. 13.7 events per 100 patient-years, P = 0.314), while most of these events terminated spontaneously. One-third of the patients with extended WCD use further improved their EF and they were not implanted with an ICD, with similar rates among ischaemic and non-ischaemic patients.ConclusionsIn WEARIT-II, patients with extended WCD use >90 days remain at risk for ventricular arrhythmia events. One-third of the patients with WCD use >90 days further improved their EF, avoiding the need to consider ICD implantation.

Aims Despite our prior report suggesting heart failure (HF) risk reduction from cardiac resynchronization therapy with defibrillator (CRT‐D) in mild HF patients with higher left ventricular ejection fraction (LVEF > 30%), data on mortality benefit in this cohort are lacking. We aimed to assess long‐term mortality benefit from CRT‐D in mild HF patients by LVEF > 30%. Methods and results Among 1274 patients with mild HF and left bundle branch block enrolled in MADIT‐CRT, we analysed long‐term effects of CRT‐D vs. implantable cardioverter defibrillator (ICD) therapy only, and reverse remodelling to CRT‐D (left ventricular end‐systolic volume percent change ≥ median at 1 year), on all‐cause mortality and HF for the LVEF ≤ 30% and LVEF > 30 subgroups using Kaplan–Meier and Cox analyses. During long‐term follow‐up, CRT‐D vs. ICD was associated with reduction in all‐cause mortality in both patients with LVEF > 30% and LVEF ≤ 30% [hazard ratio (HR) 0.47, 95% confidence interval (CI) 0.25–0.85, P = 0.036 vs. HR 0.69, 95% CI 0.49–0.98, P = 0.013, interaction P = 0.261]. The efficacy of CRT‐D vs. ICD only to reduce HF was similar in those with LVEF above and below 30% (HR 0.36, 95% CI 0.35–0.61, P < 0.001 vs. HR 0.46, 95% CI 0.35–0.61, P < 0.001; interaction P = 0.342). Patients with CRT‐D‐induced reverse remodelling had significant mortality reduction when compared to ICD, with either LVEF > 30% or LVEF ≤ 30% (HR 0.17 and 0.39), but no mortality benefit was seen in patients with less reverse remodelling. HF events, however, were reduced in both CRT‐D‐induced high and low reverse remodelling vs. ICD only, in both LVEF subgroups. Conclusions In MADIT‐CRT, left bundle branch block patients with higher LVEF (> 30%) derive long‐term mortality benefit from CRT‐D when exhibiting significant reverse remodelling. Clinical Trial registration: http://ClinicalTrials.gov ID NCT00180271, NCT01294449, and NCT02060110

No abstract

Patients with more severe HF are at increased risk for inappropriate ICD therapy, particularly ATP due to arrhythmias < 200 beats/min. Novel programming with high-rate cut-off or delayed detection reduces inappropriate ICD therapies in both mild and moderate HF.