Ventricular tachycardia burden reduction after substrate ablation: predictors of recurrence.

Abstract Background Substrate-based ventricular tachycardia (VT) ablation is a first-line treatment in patients with structural cardiac disease with sustained VT refractory to medical therapy. Despite technological improvements and increased knowledge of VT substrate, recurrence is still frequent. There is a lack of published data about the possible reduction in the VT burden after ablation despite recurrence. Objective To assess the VT burden reduction during long-term follow-up after substrate ablation and to identify predictors of VT recurrence. Methods We analyzed 234 consecutive procedures of VT ablation in 207 patients (age:63±14.9 years, males:92%, ischemic heart disease:65%) who underwent substrate ablation in a single center from 2013 to 2018. Results After a follow-up of 3.14±1.8 years, the VT recurrence rate was 41.4%. Overall, a 99.6% reduction in the VT burden (preprocedural:3.546[1.347-13.951] vs postprocedural:0.001[0-0.689] median VT episodes per year, p=0.001) and a 96.3 % decrease in ICD shocks (preprocedural:1.145[0.118-4.467] vs postprocedural:0.042[0-0.111] per year, p=0.017) were observed. In the subgroup of patients who experienced VT recurrences, the VT burden also decreased by 69.2 % (median of the VT episodes per year: preprocedural 2.876[1.105-8.801] vs postprocedural 0.882[0.505-2.283], p Conclusions Despite high rate of recurrence in long-term follow-up, substrate-based VT ablation is related to a great reduction in the VT burden and a decrease in ICD therapies. A lower ejection fraction and persistence of late potentials are predictors of recurrence.