Examination of Explanted Heart After Radiofrequency Ablation for Intractable Ventricular Arrhythmia

Abstract

Intractable ventricular tachycardia (VT) and ventricular fibrillation (VF), often referred to as electrical storm (ES), is a life-threatening emergency requiring immediate intervention.1 Patients presenting with ES often suffer from severe cardiomyopathy but may have structurally normal hearts with ion channelopathy. Common triggers of ES include myocardial ischemia, acute congestive heart failure, electrolyte abnormalities, and drug toxicity. Patients with left ventricular assist devices (LVADs) frequently develop ventricular arrhythmia and ES refractory to antiarrhythmic therapy.1 One study found that sustained VT or VF occurred in 52% of patients with a continuous-flow LVAD (HeartMate II).2 Although LVAD therapy can prevent hemodynamic collapse resulting from sustained ventricular arrhythmia, patients may develop hemodynamic instability and decreased flow rates as a result of right ventricular dysfunction. If VT/VF cannot be controlled with antiarrhythmic therapy, then urgent electrophysiological study and ablation are indicated. In this unique report, we describe a successful substrate ablation of recurrent drug refractory ES in a patient with a HeartMate II LVAD awaiting …