Sustained ventricular tachycardia of left, right or both bundle branch block morphology in patients with Arrhythmogenic Cardiomyopathy

Aims

In arrhythmogenic cardiomyopathy (ACM) sustained monomorphic ventricular tachycardia (VT) typically displays left bundle branch block (LBBB) morphology. Sustained VT with right bundle branch block (RBBB) morphology is very rare despite the frequent left ventricular involvement. The present study sought to assess the prevalence of spontaneous sustained LBBB-VT, RBBB-VT or both as well as clinical and genetic differences associated with these VT types.

Methods and results

Twenty-six centers from 11 European countries provided information on 952 patients with ACM and >1 episode of sustained VT observed during the patients' clinical course. VT was classified as: LBBB-VT; RBBB-VT or LBBB+RBBB-VT.

Among 952 patients, 881 (92.5%) had LBBB-VT alone, 71 (7.5%) had RBBB-VT [alone in 42 (4.4%) patients or with LBBB-VT in 29 (3.0%) patients]. Male prevalence was 90.5%, 79.2% and 55.9% in the RBBB-VT, LBBB-VT and LBBB+RBBB-VT groups, respectively (P=0.001). Patients' age at first VT did not differ amongst the 3 VT groups. ICD implantation was more frequent for the RBBB-VT and the LBBB+RBBB groups (≈90% each) vs. 67.9% for the LBBB-VT group (P=0.001). Death incidence (9.5%–17.2%) was not significantly different between the 3 groups (P=0.425). Plakophylin-2 mutations predominated in the LBBB-VT and LBBB-VT+RBBB-VT groups (47.2% and 27.3%, respectively) and Desmoplakin mutations in the RBBB-VT group (36.7%).

Conclusion

This large European survey demonstrates: 1) Sustained RBBB-VT is documented in 7.5% patients with ACM; 2) Males markedly predominate in the RBBB-VT and LBBB-VT groups but not in the LBBB+RBBB VT group; 3) Distribution of desmosomal mutations appears to be different in the 3 VT groups.

Funding Acknowledgement

Type of funding source: None

Determinants and prognostic significance of focal myocardial fibrosis by cardiac magnetic resonance imaging in patients with mitral valve prolapse

Background

Mitral valve prolapse (MVP) is a frequent disease that can be complicated by mitral regurgitation (MR), heart failure, arterial embolism, rhythm disorders and death.

Purpose

We sought to evaluate the correlates of late gadolinium enhancement (LGE), and the prognostic significance of ventricular size, function, and LGE by cardiac magnetic resonance (CMR) imaging on cardiovascular morbi-mortality in patients with MVP

Methods

We included 426 patients (54±15 years, 57% male) with MVP (trace to severe MR) between 2010 and 2019 who underwent a comprehensive echocardiography and CMR imaging. Gadolinium was injected in 411 (96%) patients. The main outcome endpoint was a composite endpoint of cardiovascular death, heart failure, new onset atrial fibrillation or arterial embolism, censored at the time of mitral valve intervention.

Results

Among the 411 patients, LGE+ was found in 118 (29%; 100 myocardial wall including 78 basal inferolateral midwall, 30 papillary muscles) and was more frequent with worse MR volume and LV remodeling. Correlates of LGE in multivariable analysis were LV mass index (OR 1.02, P=0.008), moderate-severe MR (OR 2.15, P=0.017) and coronary artery disease (OR 5.8, P=0.013). At 4 years, survival without cardiovascular events was decreased in patients with LGE+ (50.0±11.9 vs 73.5±6.3%, p<0.0001). In a stepwise multivariable analysis including classical predictors of outcome, grade of MR, LA volume index and the presence of LGE on CMR imaging (HR: 2.15 [1.15–4.02], P=0.017) were associated with impaired event-free survival.

Conclusion

CMR imaging provides additional information to echocardiography in the clinical work-up of MVP. Localized LV myocardial fibrosis is a predictor of cardiovascular event in MVP patients.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): DGOS (PHRCI), Fondation Cœur et Recherche

Efficacy of deep sedation for patients with intractable electrical storm refractory to anti-arrhythmic drugs

Background

Sympathetic overactivity is implicated in the initiation and maintenance of electrical storm (ES). Deep sedation has empirically been considered as an efficient therapeutic option to blunt sympathetic tone and control ES.

Purpose

The aim of this multicenter study was to determine the efficacy of deep sedation in patients presenting intractable ES refractory to anti-arrhythmic drugs.

Methods

Patients requiring deep sedation for refractory ES from January 1st 2007 to July 31st 2018 were retrospectively included in 13 centers. The primary endpoint was the rate of acute response to sedation, defined as ES termination within 15 minutes after deep sedation.

Results

Among the 116 patients, 55 (47.4%) had ES termination within 15 minutes and were considered “acute responders” to deep sedation. Clinical signs of congestive heart failure before deep sedation (OR=3.31, 95% CI:1.001–10.97, p=0.049) was the only independent predictor of non-acute response. Twenty-one non-acute responders (34.4%) had an extracorporeal membrane oxygenation (ECMO) implanted. Non-acute responders had a significantly lower in-hospital survival (Log-rank, p=0.010). ECMO implantation did not influence survival in non-acute responders to sedation. Acute response to deep sedation was an independent protector of in-hospital mortality, decreasing by 73% the risk of death (OR 0.27; 95% CI:0.10–0.70, p=0.008).

Conclusion

To the best of our knowledge, this multicenter study is the first analysis of the efficacy of deep sedation in patients with intractable ES refractory to anti-arrhythmic drugs, and demonstrating the positive impact of “acute response” on in-hospital survival.

Funding Acknowledgement

Type of funding source: None