Mortality after catheter ablation of structural heart disease related ventricular tachycardia.

Background: There is a paucity of data describing mortality after catheter ablation of ventricular tachycardia (VT).

Objectives: We describe the causes and predictors of cardiac transplant and/or mortality following catheter ablation of structural heart disease (SHD) related VT.

Methods: Over 10-years, 175 SHD patients underwent VT ablation. Clinical characteristics, and outcomes, were compared between patients undergoing transplant and/or dying and those surviving.

Results: During 2.8 (IQR 1.9-5.0) years follow-up, 37/175 (21%) patients underwent transplant and/or died following VT ablation. Prior to ablation, these patients were older (70.3 ± 11.1 vs. 62.1 ± 13.9 years, P = 0.001), had lower left ventricular ejection fraction ([LVEF] 30 ± 12% vs. 44 ± 14%, P < 0.001), and were more likely to have failed amiodarone (57% vs. 39%, P = 0.050), compared to those that survived. Predictors of transplant and/or mortality included LVEF≤35% (HR 4.71 [95% CI 2.18-10.18], P < 0.001), age ≥ 65 years (HR 2.18 [95% CI 1.01-4.73], P = 0.047), renal impairment (HR 3.73 [95% CI 1.80-7.74], P < 0.001), amiodarone failure (HR 2.67 [95% CI 1.27-5.63], P = 0.010) and malignancy (HR 3.09 [95% CI 1.03-9.26], P = 0.043). Ventricular arrhythmia free survival at 6-months was lower in the transplant and/or deceased, compared to non-deceased group (62% vs. 78%, P = 0.010), but was not independently associated with transplant and/or mortality. The risk score, MORTALITIES-VA, accurately predicted transplant and/or mortality (AUC: 0.872 [95% CI 0.810-0.934]).

Conclusions: Cardiac transplant and/or mortality after VT ablation occurred in 21% of patients. Independent predictors included LVEF≤35%, age ≥ 65 years, renal impairment, malignancy, and amiodarone failure. The MORTALITIES-VA score may identify patients at high-risk of transplant and/or dying after VT ablation.