Catheter ablation of drug refractory electrical storm in patients with ischemic cardiomyopathy: A single center experience

OBJECTIVE: Electrical storm (ES) is a life-threatening pathology that requires immediate and effective treatment due to increased morbidity and mortality. Catheter ablation (CA) is an effective therapeutic option, particularly in patients with drug resistant ventricular arrhythmia episodes. These procedures should only be performed in highly specialized and experienced centers. Here we aimed to assess safety and efficacy of CA in a relatively large cohort with ES in our tertiary center hospital. METHODS: A total of 44 patients (90.9% male; mean age: 59.7±10.3 years) with ischemic cardiomyopathy undergoing CA for drug-refractory ES were prospectively evaluated. Procedures were performed using non-contact and electro-anatomic mapping systems. Long-term follow-up analysis addressed the predictors of ES recurrence and cardiac mortality. RESULTS: Acute success rates for clinical and non-clinical VTs were 90.8% and 55.5%, respectively. A mean follow-up at 28±11 months revealed cardiac mortality in 8 (18%) patients, 39 (88.6%) patients were free from the ES, and 24 (55%) patients remained free from both ES and paroxysmal VT episodes. In multivariate regression analysis, recurrence of ES (OR=3.11, 95% CI: 1.65-4.62, p=0.001), LVEF, and serum creatinine were found as independent predictors of cardiac mortality. In addition, substrate based ablation, implantation of ICD for secondary prophylaxis, LVEF, and serum creatinine were good predictors of ES recurrence. CONCLUSION: Catheter ablation for ventricular arrhythmias in the course of ES in patients with ischemic cardiomyopathy is safe with an acceptable success rate. (Anatol J Cardiol 2016; 16: 159-64)