Catheter Ablation -> Ventricular Arrhythmias -> Clinical Trials / Outcomes D-PO05 - Poster Session V (ID 39) Poster

D-PO05-202 - Outcome Of Catheter Ablation In Dilated Cardiomyopathy Related To Titin Variants And Prognostic Significance Of The Type Of Ventricular Arrhythmia At Presentation: Results From A Multicenter Experience (ID 1307)


Background: Titin variants (TTNvar) are the most prevalent inherited causes of dilated cardiomyopathy (DCM). Different ventricular arrhythmia (VA) subtypes have been reported during the course of the disease that may require catheter ablation (CA).
Objective: To analyze the long-term outcomes after CA of patients with TTNvar presenting with VAs and to study the prognostic relevance of the type of VA at presentation.
Methods: Twenty-two consecutive patients (pts) with pathogenic TTNvar referred for CA of VAs from 4 centers were included (mean age 56±11years, LVEF 38±13%, 77%male). Pts with premature ventricular contractions (PVCs) were compared to pts with monomorphic sustained VTs (MSVTs). Complete procedural success was defined as non-inducibility of any VT or reduction of PVC-burden ≥80% after CA. Patients were followed for VT-free survival.
Results: Eight pts were referred for CA of PVCs and 14 for MSVTs. Patients age, baseline LVEF and distribution of variant types were similar between groups. PVCs and VTs were attributed to intramural, basoseptal substrates in 20pts(91%). Non-complete procedural success was 73% (16/22; PVC-phenotype:7[88%] vs. VT-phenotype:9[64%], P=0.5). Median FU was 29(11-58) months. One patient was lost of FU and excluded from outcome analysis. Eleven pts (55%) experienced MSVT during FU: 0/8(0%) PVC-phenotype vs. 11/13(85%) VT-phenotype, P<0.001. In addition, 4pts(29%) died (all VT-phenotype).
Conclusion: Acute success of CA for both VAs subtypes in TTNvar carriers is low. However, long-term VT-free survival was excellent in patients with PVCs but poor in those with MSVT, suggesting that the type of VA at presentation is an important prognostic marker.