Cardiac Recovery During Mechanical Assist Device Support

It is estimated that approximately 100,000 patients in the United States with advanced heart failure might benefit from cardiac transplantation, while donors are available for only 2000 recipients each year. Left ventricular assist devices (LVADs) are used both for bridge to transplantation and for long term support in patients ineligible for transplant. Both cardiac transplantation and long term LVAD therapy are limited by the complications of immunosuppression and device malfunction. Currently, a major focus of investigation in advanced heart failure is the temporary use of LVADs as a bridge to recovery of the native heart. While end-stage heart failure was once thought to be irreversible, research now suggests that LVAD support may lead to both cellular and functional recovery. Ultimately, patients with advanced cardiac disease might be managed with temporary mechanical support combined with pharmacological and cellular therapies, in place of cardiac transplantation or long term LVAD support. In this paper we review the evidence demonstrating the impact of LVAD support on the pathophysiology of end stage heart failure. Furthermore, we outline the clinical evidence for cardiac recovery seen in LVAD patients. Finally, we describe techniques to measure cardiac function during LVAD support and the criteria that have been suggested to select patients for device explantation for recovery.