Impact of Catheter Ablation of Electrical Storm on Survival: A Propensity Score-Matched Analysis

Abstract

Background: Electrical storm (ES) is a life-threatening condition, associated with substantial early and subacute mortality. Catheter ablation (CA) is a well-established therapy for ES. However, data regarding the impact of CA on the short-term and midterm survival of patients admitted for ES remain unclear.

Objectives: This multicenter study aimed to investigate the impact of CA of ES on survival outcomes, while accounting for key patient characteristics associated with treatment selection.

Methods: A propensity score-matching (PSM) analysis was performed on 780 consecutive patients admitted for ES in 4 tertiary centers. PSM (1:1) based on the main characteristics associated with the use of CA or medical therapy alone was performed, resulting in 2 groups of 288 patients.

Results: After PSM, patients who underwent CA (n = 288) and those treated with medical therapy alone (n = 288) did not present any significant differences in the main demographic characteristics, ES presentation, and management. Compared with medical therapy alone, CA was associated with a significantly lower rate of ES recurrence at 1 year (5% vs 26%; P < 0.001). Similarly, CA was associated with a higher 1-year (91% vs 81%; P < 0.001) and 3-year (78% vs 71%; P = 0.017) survival after discharge. In subgroup analyses, effect of ablation therapy remained consistent in patients older than 70 years of age (HR: 0.39; 95% CI: 0.24-0.66), with substantial efficacy in patients with a LVEF <35% (HR: 0.39; 95% CI: 0.27-0.59).

Conclusions: In propensity-matched analyses, this large study shows that CA-based management of patients admitted for ES is associated with a reduction in mortality compared with medical treatment, particularly in patients with a low ejection fraction.

Keywords: antiarrhythmics; catheter ablation; death; electrical storm; management; medical therapy; mortality; radiofrequency; survival; ventricular arrhythmia.