title: Catheter ablation for the treatment of electrical storm in patients with implantable cardioverter-defibrillators: short- and long-term outcomes in a prospective single-center study.
abstract: BACKGROUND
  Electrical storm (ES) caused by recurrent episodes of ventricular tachycardia (VT) can cause sudden death in patients with implantable cardioverter-defibrillators and adversely affects prognosis in survivors. Catheter ablation has been proposed for treating ES, but its long-term effect in a large population has never been verified.
  
  
  RESULTS
  Ninety-five consecutive patients with coronary artery disease (72 patients), idiopathic dilated cardiomyopathy (10 patients), and arrhythmogenic right ventricular dysplasia/cardiomyopathy (13 patients) undergoing catheter ablation for drug-refractory ES were prospectively evaluated. Short-term efficacy was defined by a complete protocol of programmed electric stimulation and by in-hospital outcome; long-term analysis addressed ES recurrence, cardiac mortality, and VT recurrence. Pleomorphic/nontolerated VTs required electroanatomic and noncontact mapping in 48 and 22 patients, respectively, and percutaneous cardiopulmonary support in 10 patients. An epicardial approach was used in 10 patients. After 1 to 3 procedures, induction of any clinical VT(s) by programmed electrical stimulation was prevented in 85 patients (89%). ES was acutely suppressed in all patients; a minimum period of 7 days with stable rhythm was required before hospital discharge. At a median follow-up of 22 months (range, 1 to 43 months), 87 patients (92%) were free of ES and 63 patients (66%) were free of VT recurrence. Eight of 10 patients with persistent inducibility of clinical VT(s) had ES recurrence; 4 of them died suddenly despite appropriate implantable cardioverter-defibrillator intervention. All together, 11 of 95 patients (12%) died of cardiac-related reasons. In the group of patients presenting with all clinical VTs acutely abolished, no ES recurrence was documented, and cardiac mortality was significantly lower compared with the group of patients showing > or = 1 clinical VT still inducible after catheter ablation.
  
  
  CONCLUSIONS
  Advanced strategies of catheter ablation applied to a large population of patients are effective in the short-term treatment of ES. By preventing ES recurrence, catheter ablation may play a protective role over the long term and, together with long-term pharmacological therapy, may favorably affect cardiac mortality.
authors.affiliation: Arrhythmia Department, Institute of Cardiology, University of Milan, IRCCS-Centro Cardiologico Monzino, Via Parea, 4, 20138-Milan, Italy. corrado.carbucicchio@ccfm.it
authors.forename: Corrado
authors.initials: C
authors.lastname: Carbucicchio
authors.forename: Matteo
authors.initials: M
authors.lastname: Santamaria
authors.forename: Nicola
authors.initials: N
authors.lastname: Trevisi
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Maccabelli
authors.forename: Francesco
authors.initials: F
authors.lastname: Giraldi
authors.forename: Gaetano
authors.initials: G
authors.lastname: Fassini
authors.forename: Stefania
authors.initials: S
authors.lastname: Riva
authors.forename: Massimo
authors.initials: M
authors.lastname: Moltrasio
authors.forename: Manuela
authors.initials: M
authors.lastname: Cireddu
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Veglia
authors.forename: Paolo
authors.initials: P
authors.lastname: Della Bella
mesh_terms: D000368:Aged; D017115:Catheter Ablation / Q000379:methods*; D017147:Defibrillators, Implantable / Q000009:adverse effects*; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D016879:Salvage Therapy / Q000379:methods; D055502:Secondary Prevention; D017180:Tachycardia, Ventricular / Q000209:etiology / Q000401:mortality / Q000517:prevention & control / Q000628:therapy*; D016896:Treatment Outcome