Contribution of ventricular assist devices to the recovery of failing hearts: a review and the Berlin Heart Center Experience

Ventricular assist-device (VAD) implantation is a life-saving therapy which will later become either a bridge-to-transplantation or definitive therapy if heart transplantation (HTx) is not possible. VAD-supported failing hearts often recover at the molecular and cellular level, but translation of these changes into functionally stable cardiac recovery allowing long-term HTx/VAD-free outcomes after VAD removal is relatively rare, related to the aetiology, severity, and duration of myocardial damage. The reason for the discrepancy between high recovery rates on cellular and molecular levels and the low rate of cardiac recovery allowing VAD explantation is unknown. For selected patients VAD explantation is feasible. HTx/VAD-free outcomes for >15 years are possible even if recovery remains incomplete and the underlying cause for VAD implantation was idiopathic dilated cardiomyopathy. Echocardiography and right heart catheterization are necessary to assess clinically relevant cardiac recovery. Certain echo parameters appeared highly predictive for post-weaning cardiac function and reliable for weaning decisions. The elective therapeutic use of VADs for heart failure (HF) reversal in its earlier stages is a future goal possibly achievable by development of tools to predict HF reversibility already before VAD implantation and increase the number of weaning candidates by improvement of adjunctive therapies to optimize unloading-promoted recovery. The present article summarizes the knowledge about unloading-promoted myocardial recovery and reviews the available data on its clinical relevance, its post-explant stability, and its assessment for decision-making in favour of or against VAD explantation. The review also aims to provide a theoretical and practical basis for clinicians intending to be engaged in this field.