N. Auquier

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.

Pacemaker memory in post-TAVI patients: Who should benefit from permanent pacemaker implantation?

One of the most frequent complications of transcatheter aortic valve implantation (TAVI) is the occurrence of atrioventricular (AV) conduction disorders secondary to AV node or His bundle injury leading to permanent pacemaker implantation (PPI). The objective was to quantify the rate of ventricular pacing (VP), according to post‐TAVI indication for PPI using recorded pacemaker memory.

0463: Significant decrease in redo procedure rate following paroxysmal atrial fibrillation ablation with second generation of cryoballoon as compared to first generation

Background Ablation of paroxysmal atrial fibrillation (PAF) using a cryo-balloon catheter is currently expanding. The success rate of ablation with the Arctic Front® cryoballoon has been found to be similar to what was observed with radiofrequency catheter.The recent use of the new catheter Arctic Front Advance® seems to improve this performances. We postulate that this new generation of catheter could decrease the rate of redo procedures and maintain more effectively the pulmonary vein (PV) isolation. Methods From January 2009 to April 2014, we prospectively collected data regarding all consecutive patients referred for PAF ablation with cryoballoon technology at our institution. Patients were assigned either to 1stCB group if the arctic front catheter was used (from January 2009 to June 2012) or to the 2ndCB group if the arctic front advance catheter was used (from jully 2012 to April 2014). We performed a follow up of one year in each group and we compared the number of redo procedures and their characteristics. Results We included 106 patients in borh groups.Characteristics of the population are described in table 1. The rate of redo procedures at one year was significantly lower in the 2ndCB group (9.4% vs 37%; p When a redo procedure was performed, the average number of reconnected PV was 2.2 in the 2ndCB group and 2.8 in 1stCB group (p=0.14). In the 2ndCB group, PV reconnection occurred more frequently the inferior PVs (right inferior PV=90%, left inferior PV=63%, right superior PV 30% and left superior PV=15%). This difference of distribution is less pronounced in the 1stCB group (LIPV=90%, RIPV=65%, RSPV=58% and the LSPV=55%). Conclusion The new generation of cryoballoon significantly decreased the rate of redo procedures at one year. Using the second generation CB, pulmonary vein reconnection was more frequently observed with the inferior PV. This could probably be explained by the anatomical characteristics of these veins (figure next page). Download : Download high-res image (132KB) Download : Download full-size image Abstract 0463 – Figure: Characteristics of the population

0299 : Use of clinical follow-up and pacemaker memories to define predictors of complete atrio-ventricular block or sudden death after balloon- expandable transcatheter aortic valve implantation

Backgrounds Predictors of atrio-ventricular block (AVB) after transcatheter aortic valve implantation (TAVI) have been described as those leading to syncope or permanent pacemaker implantation (PPI), and thus have been assimilated to criterias used by the investigators for pacemaker implantation. Aims Evaluating the true predictors of AVB following TAVI, using clinical follow-up and devices’ memories. Methods Between 2011 and 2013, 213 patients without previous PPI underwent TAVI with an Edwards SAPIEN XT balloon-expandable valve using a femoral approach, in our institution. All patients had continuous cardiac rhythm monitoring ≥24 hours after TAVI. ECG was performed the following 2 days after TAVI, and 1 month later. Median follow-up for pacemaker interrogation was 8 months. Results Complete AVB occurred in 22 patients (10.3%), sudden death in 8 patients (3.8%). Pacemaker was implanted in 26 patients (12.2%). For 20 of them (77%), pacemaker memories showed complete AVB episodes or ≥2% ventricular pacing, despite the use of a minimizing ventricular pacing algorithm. Results of the multivariate analysis are shown below. Table No complete AVB or Sudden death (%) Complete AVB or Sudden death (%) Odds Ratio (95% CI) P Preexisting RBBB 15 (8) 13 (43) 6.62 (1.7 - 26.3) 0.007 New persistant LBBB 14 (8) 8 (33) 10.1 (2.5 – 41.7) 0.001 1st degree AVB after TAVI 34 (27) 9 (56) 3.48 (1.1 – 11.2) 0.04 LBBB: left bundle branch block; RBBB: right bundle branch block Conclusions Our findings confirmed pre-existing RBBB and new persistent LBBB as predictors of AVB following TAVI. We also demonstrated here for the first time, first degree AVB is an independent predictive factor of severe conduction disorders after TAVI.

0536: Use of 2nd generation cryoballoon with reduced dosing strategy is superior to 1st generation cryoballoon for paroxysmal atrial fibrillation ablation

Background With the technical properties of the 2nd generation (Arctic Front Advance, AFA) cryoballoon (CB), we postulated we could reduce complication rate without impairing efficacy in the treatment of paroxysmal atrial fibrillation if we stop the bonus application. Method Since January 2011, all patients referred to our institution for ablation of symptomatic drug refractory paroxysmal atrial fibrillation were included (n=129). Until June 2012, the ablation was performed with the Arctic Front cryoballoon (AF-CB) with application of 4mm bonus freeze after PVI (n=47). From July 2012 to December 2013, the ablation procedure was performed with the AFA-CB, without bonus freeze after PVI in 82 patients. All patients were seen at 4 to 6 month follow-up. They underwent at least 1 Holter monitoring in the post-operative period (2-4 month after ablation). Mid-term clinical success was defined by the association of sinus rhythm on ECG and Holter monitoring and lack of symptoms. Results Compared to the AFCB group, there was a significant reduction of the procedure time (131 min vs 95 min; p Using our definition for success, the mid-term success rate was higher in the AFA-CB group as compared with that of in the AF-CB group (78% vs 53% p = 0.01; CI [1,3 - 6,5]). Significant complications occurred in 9% in the AFA-CB group versus 13% in the AF-CB group (p = 0.44). There was no difference regarding the rate of phrenic nerve palsy (7% AF-CB group vs 5% AFA-CB group;p=0.24). Conclusion The lack of a bonus freeze application after PVI allows to significantly reducing the procedure time and the X-ray exposure. Even when using a reduced dosing strategy, our study shows the AFA-CB leads to a better outcome as compared to the AF-CB.