The outcome spectrum for Dilated Cardiomyopathy and Ventricular Tachycardia: results from the prospective, multicenter, DCM-VT ablation study

Abstract

Abstract Funding Acknowledgements Type of funding sources: Private company. Main funding source(s): The study was partially supported by an investigator initiated grant from Biosense Webster (a Johnson & Johnson company) Background Recurrent sustained ventricular tachycardia (VT) due to nonischemic dilated cardiomyopathy (DCM) is difficult to treat and long-term outcome data are limited. Objective We aimed to identify predictors for mortality or heart transplantation (MHT) and VT recurrence. Methods Consecutive DCM patients accepted for VT catheter ablation (RFCA) in 9 centers were prospectively enrolled and followed. Results Of 281 consecutive patients (age 60±13yrs, 85% men, LVEF 36±12%) 35% had VT storm, 20% incessant VT, and 68% failed amiodarone. During a median follow-up of 21 (IQR 6-30) months after RFCA (epicardial in 58%, no RFCA due to inaccessible target in 6.4%), 67(24%) patients died/underwent HT and 138(49%) had VT recurrence (45 within 30 days defined as early); the cumulative 4-year rate of VT or MHT was 70% and of MHT 38%. In multivariable analysis predictors of MHT were early VT recurrence (HR 2.92 (CI1.37-6.21), p<0.01), amiodarone at discharge (HR 3.23 (CI1.43-7.33, p<0.01), renal dysfunction (HR 1.92 (CI1.01-3.64), p=0.046), and LVEF (HR 1.36 (CI 1.0-1.84), p=0.052). A LVEF ≤32% was the optimal threshold to identify patients at risk for MHT (AUC 0.75). MHT per 100 person-years was 40.4 after early VT recurrence and significantly higher, compared to 14.2 after later VT recurrence and to 8.5 after RFCA with no VT recurrence (both p<0.01). Mortality rates for patients with VT recurrence after 30 days were not significantly higher than for patients with no VT recurrences Patients with early recurrence and LVEF≤32% had a 1-year MHT rate of 55% (figure). VT recurrence was predicted by prior ICD shocks, basal antero-septal VT origin, and procedural failure but not LVEF. Conclusion DCM patients needing RFCA for VT are a high-risk group. Following RFCA half remain free of VT recurrences. Early VT recurrence with LVEF<0.32 identifies those with a very high risk and screening for mechanical support/ HT should be considered. Late VT recurrence after RFCA does not predict worse outcome.