Efficacy of Mechanical Circulatory Support Devices for Termination of Drug – Refractory Sustained Ventricular Tachycardia

Abstract

Management of patients with sustained ventricular tachycardia or ventricular fibrillation (VT/VF) refractory to maximal medical therapy poses a challenging clinical situation because remaining options are limited. Mechanical circulatory support devices such as intra-aortic balloon pumps (IABP) and left ventricular assist devices (LVAD) have been used in this setting not only to provide hemodynamic stability, but also for arrhythmia management. However, data to support their placement in this clinical situation is limited. We conducted a retrospective observational study investigating the efficacy of mechanical circulatory assist devices to terminate drug refractory sustained VT/VF. We identified 17 patients (76% male; age 65.2 ± 10.4 years; LVEF (%) 31 ± 20) with sustained VT/VF who required IABP or LVAD placement for this purpose. Sustained VT/VF patients on maximal doses of intravenous amiodarone were categorized based on a “positive response” to device placement, which was defined as termination of VT/VF within 24 hours with no recurrences. Four patients (24%) had a positive response to device placement. In-hospital survival was 100% (4/4) for responders and 31% (4/13) for nonresponders (p = 0.015). Non-responders were more likely to have an elevated creatinine (mg/dL) (2.02 ± 0.92 vs 1.12 ± 0.40; p = 0.03) and a prior history of sustained VT/VF (p = 0.012). Other comparison points including age, sex, left ventricular ejection fraction, presence of coronary artery disease, and history of myocardial infarction were not different between responders and non-responders. In conclusion, the findings suggest that placement of circulatory assist devices for sustained VT/VF refractory to medical treatment has a beneficial effect to terminate VT/VF but its efficacy may be limited to patients with no prior history of sustained VT/VF and no renal insufficiency.