Ablation of Ventricular Tachycardia Storm in a Patient with Biventricular Mechanical Support Devices - A Case Report

Abstract

Background Ventricular tachycardia (VT) has been described in patients who have undergone implantation of ventricular assist devices (VAD). Mechanisms for VT in these patients include scar-mediated reentry, bundle branch reentry, and mechanically-induced arrhythmia related to scar caused by VAD inlet cannula placement or suction events. While the hemodynamic support offered by VAD's can mitigate the harmful effects of ventricular tachyarrhythmias, morbidity can arise from outcomes including RV failure. VT ablation has been utilized with some success in these patients though data in this area is scarce, especially in those with biventricular support devices. Case Report We present a case of a 47 year-old man with a history of hypertension, tobacco and cocaine abuse presenting with STEMI. Despite emergent catheterization with PCI to proximal LAD lesion, he developed cardiogenic shock requiring intra-aortic balloon pump placement. He subsequently suffered V Fib arrest necessitating upgrade to VA-ECMO. Due to persistent biventricular failure with inability to wean support, he was transitioned to durable left ventricular support (Heartmate 3, Abbott) and temporary right ventricular support (Protek Duo, TandemLife). Despite durable support, he remained in VT refractory to antiarrhythmic agents (Amiodarone, Lidocaine, Procainamide), multiple cardioversions, and stellate ganglion block. Given incessant VT leading to RV failure and compromising RVAD removal, the decision was ultimately made to proceed with VT ablation. The patient underwent extensive substrate-based ablation and ablation of the right bundle and left posterior fascicle for bundle branch reentry and interfascicular VT complicated by transient AV block requiring TVP insertion. Other complicating factors involved in this procedure included gaining access and manipulating ablation catheters given presence of prior devices including the LVAD cannula. At the end of the procedure the patient had no further inducible VT. He was successfully weaned off of RVAD support after the ablation. His hospital course was complicated by recurrent slower VT which was successfully managed with medical therapy. Conclusions Our case highlights several complicating factors in managing ventricular tachyarrhythmias in patients with mechanical circulatory support devices. These include limitations to medical management due to side effect profiles or refractoriness, coordination of multiple disciplines (advanced heart failure, EP, VAD team, anesthesia), as well as barriers to successful ablation including technical difficulty given the presence of other devices, the desire to avoid invasive procedures in patients susceptible to or suffering from systemic infection, and high recurrence rates. In this specific case VT ablation was successful in facilitating the goal of weaning the patient off of RVAD support.