Catheter ablation reduces ventricular tachycardia burden in patients with arrhythmogenic right ventricular cardiomyopathy: insights from a north-western French multicentre registry.

Aims: Studies assessing radiofrequency ablation (RFA) of ventricular tachycardia (VT) in arrhythmogenic right ventricular cardiomyopathy (ARVC) report VT recurrences, but have not evaluated the impact of RFA on relevant clinical events during follow-up. We aimed to investigate relevant RFA outcomes in a multicentric registry. Methods and results: This study included 49 patients with ARVC (46 with definite diagnosis, 3 with borderline diagnosis according to revised Task Force Criteria) who underwent 92 RFA procedures (83 endocardial, 9 combined endo-epicardial) between 1999-2015. Ventricular tachycardia recurrences and VT burden were assessed after each procedure or after the last RFA. Over a mean follow-up of 64 ± 51 months, VT-free survival was 37% at 1 year, 19% at 5 years, and 14% at 10 years. Ventricular tachycardia burden was significantly reduced after one procedure (23 vs. 11 VT episodes/year, P < 0.01) and after the last RFA (14 vs. 2 VT episodes/year, P < 0.01). Over a mean follow-up of 49 ± 52 months, clinical response after the last RFA (freedom from sudden cardiac death, VT requiring hospitalization, or heart transplantation) was 86% at 1 year, 69% at 5 years, and 60% at 10 years. Clinical response was associated with right ventricular dysfunction (RVD) and low numbers of mappable VT before the first RFA. Conclusion: RFA was predominantly targeted at the endocardial surface. Ventricular tachycardia recurrences were common, but few ARVC patients experienced major clinical events during follow-up. Further studies should investigate the benefit of extensive substrate ablation combined with endo-epicardial strategies.

Catheter ablation of epicardial ventricular tachycardia from the coronary venous system: Is endocardial mapping always required?

Endocardial mapping is typically considered as the first step of VT ablation procedures. Nevertheless, when the electrocardiogram is highly suggestive of an epicardial VT, a minimally invasive procedure performed exclusively via the coronary sinus might be considered. This straightforward approach avoids all potential complications associated with access to the left ventricular endocardium, the aortic root, and the pericardial space.

Percutaneous left atrial appendage closure improves left atrial mechanical function through Frank-Starling mechanism.

BACKGROUND: Modifications in left atrial (LA) flow velocities after left atrial appendage (LAA) exclusion have been shown in animal and ex vivo models. In a substudy of PROTECT AF (Percutaneous Closure of the Left Atrial Appendage Versus Warfarin Therapy for Prevention of Stroke in Patients With Atrial Fibrillation), an objective improvement in quality of life was observed after LAA closure. OBJECTIVE: The purpose of this study was to investigate the impact of LAA closure on LA transport function. METHODS: Comprehensive transthoracic echocardiography evaluation (2-dimensional [2D]/3-dimensional [3D], 2D speckle tracking) was prospectively performed before and after LAA closure (at discharge and 45 days after procedure) in 33 patients. RESULTS: LAA closure was associated with a significant improvement in LA reservoir function at discharge and 45 days after the procedure with (1) increased maximum LA volume index, (2) increased 2D-LA reservoir volume and expansion index, and (3) increased 2D speckle tracking-derived peak atrial longitudinal strain (PALS) (27.9 ± 14 and 26 ± 12.6 vs 21.7 ± 10.7%, P <.0001). LAA closure was also associated with a significant improvement in LA contractile function with (1) increased LA ejection fraction and (2) increased speckle tracking-derived peak atrial contraction strain (PACS) in sinus rhythm patients (19.1 ± 6.8 and 18.1 ± 5.4 vs 14.4 ± 6.4%, P = .0006). Conversely, the slope of the relation between PACS and PALS remained unchanged (0.5 ± 0.27 and 0.53 ± 0.3 vs 0.5 ± 0.25, P = .99), thus arguing for an improvement in LA contractile function secondary to a Frank-Starling effect rather than a modification in its intrinsic contractility. CONCLUSION: LAA closure was associated with an improvement in LA mechanical function. These changes appeared to be related to a modification in loading conditions, that is, a Frank-Starling effect.

Arrhythmogenic right ventricular cardiomyopathy and left atrial tachycardia: a case report.

Little is known about atrial arrhythmias in arrhythmogenic right ventricular cardiomyopathy (ARVC). A 46-year-old man with definite ARVC presented with palpitations and exertional dyspnoea. Electrocardiogram showed a supraventricular tachycardia. Despite no prior cardiac surgery or atrial fibrillation ablation, electrophysiological study revealed a left atrial (LA) re-entrant circuit characterized by a slow fractionated potential bounded by two areas of double potentials giving a figure-of-eight pattern on activation map. Located on the LA roof within a zone of low bipolar voltages, this unusual substrate can be associated with a primitive atrial myopathy in ARVC.

Long-term outcome of implantable cardioverter-defibrillator implantation in secondary prevention of sudden cardiac death.

BACKGROUND: Little is known about the long-term outcomes of patients who receive an implantable cardioverter-defibrillator (ICD) for purely secondary prevention indications. AIMS: To assess the rates and predictors of appropriate therapies over a very long-term follow-up period in this population. METHODS: Between June 2003 and August 2006, 239 consecutive patients with structural left ventricular disease and a secondary prophylaxis indication for ICD therapy (survivors of life-threatening ventricular tachyarrhythmias) were prospectively enrolled. An extended follow-up of these patients was carried out. The primary endpoint was the occurrence of appropriate device therapy. Secondary endpoints were all-cause death, electrical storm and inappropriate therapy. RESULTS: The study population consisted of 239 patients (90% men; mean age 64±12 years; 72% ischaemic cardiomyopathy; left ventricular ejection fraction 37±12%). During a median follow-up of 7.8 (3.5-9.3) years, appropriate device therapy occurred in 139 (58.2%) patients. Death occurred in 141 patients (59%), electrical storm in 73 (30.5%) and inappropriate therapy in 42 (17.6%). Multivariable analysis identified patients whose presenting arrhythmia was ventricular fibrillation as being less likely to require appropriate device therapy than those whose presenting arrhythmia was ventricular tachycardia (sub-hazard ratio 0.62, 95% confidence interval 0.40-0.97; P=0.04). Independent predictors of all-cause death were age at implantation (P<0.0001), wide QRS complexes (P=0.024), creatinine concentration (P=0.0002) and B-type natriuretic peptide at implantation (P=0.0001). CONCLUSION: Secondary prevention ICD recipients exhibit a high risk of appropriate device therapy and death over prolonged follow-up. Patients who presented initially with ventricular fibrillation were less likely to require the delivery of appropriate device therapy.

Impact of remote monitoring on reducing the burden of inappropriate shocks related to implantable cardioverter-defibrillator lead fractures: insights from a French single-centre registry.

AIMS: Lead fractures in implantable cardioverter-defibrillator (ICD) patients may cause inappropriate shocks (ISs). An early diagnosis is essential to prevent adverse clinical events. Implantable cardioverter-defibrillator remote monitoring (RM) permits prompt detection of lead fracture. Limited data define the impact of RM on ISs specifically related to lead fracture. We sought to compare the number of ISs related to lead fracture in patients with vs. without RM follow-up. METHODS AND RESULTS: We checked the registry of our institution and collected, between July 2007 and June 2014, 115 cases of right ventricular lead fractures. All relevant data were documented from patients' files, device-interrogation printouts and electronic records, and remote transmissions databases when applicable. We assessed the ISs that were related to lead fracture. The first study endpoint was the number of ISs per shocked patient. Among the 82 patients with conventional follow-up (CFU) and the 33 patients with RM, a first IS occurred to 32.9% (n = 27) and 30.3% (n = 10, P = 0.83) of the patients, respectively. Shocked patients in the RM group underwent significantly fewer ISs with a mean of 6 ± 2 shocks per patient [median of 3.5 shocks (2-8)] than those in the CFU group with a mean of 18 ± 5 shocks per patient [median of 10 shocks (5-22), P = 0.03]. CONCLUSION: Remote monitoring helps to reduce the burden of ISs related to ICD lead fractures.