Cardiac Improvement During Mechanical Circulatory Support

Abstract

Background-Myocardial recovery after left ventricular assist device (LVAD) support has been reported. The LVAD Working Group Recovery Study was a prospective multicenter trial to assess the incidence of myocardial recovery in patients bridged to cardiac transplantation. Methods and Results-After LVAD implantation, patients were evaluated with the use of rest echocardiograms with partial LVAD support and cardiopulmonary exercise testing. Dobutamine echocardiography with hemodynamic measurements was performed in those patients with left ventricular ejection fraction Ͼ40% during resting studies.Histological analysis was performed on myocardial samples taken at LVAD implantation and explantation. Sixty-seven LVAD patients with heart failure participated in the study. 001).Tissue analysis revealed significant reductions in myocyte size, collagen content, and cardiac tumor necrosis factor-␣. Six subjects (9%) underwent LVAD explantation for recovery. Conclusions-Cardiac function improves significantly after device implantation. Although cellular recovery and improvement in ventricular function are observed, the degree of clinical recovery is insufficient for device explantation in most patients with chronic heart failure.

Left ventricular assist device as a bridge to recovery in a young woman admitted with peripartum cardiomyopathy

“…[5][6][7][8][9][10][11][12][13][14][15] Sufficient recovery of left ventricular function, allowing LVAD explantation, however, is rare and is mainly feasible in patients suffering from acute myocarditis or PPCM. 10,11,13 In these cases, the LVAD will maintain the patient's life, allowing the myocardium to recover from the underlying disease. Long-term results after explantation are favourable (one-and five-year survival rate of 86 and 78%, respectively).…”

Ventricular Assist Device: Emerging Modality for Long Term Cardiac Support

“…The ability of LVADs to support an acutely failing heart while it recovers function is well documented. 16,17,33 There are observations regarding the potential for myocardial recovery even in patients with chronic heart failure. Various studies have documented that the unloaded left ventricle undergoes a process of reverse remodeling, as categorized by multiple different indices e.g.…”

“…To date, an average of only 5%-10% of patients who undergo mechanical circulatory support demonstrate adequate recovery of ventricular function to allow device explantation. 33,34 There is also concern that prolonged mechanical unloading reduces cardiac cell function, as well as cell size, in a time-dependent manner [35][36][37][38][39][40] which may lead to myocardial atrophy. Unloading induced atrophy can be an important impediment to myocardial recovery and removal of the VADs for bridge-to-recovery, limiting the efficacy of VAD treatment.…”

Magnitude and Time Course of Changes Induced by Continuous-Flow Left Ventricular Assist Device Unloading in Chronic Heart Failure: Insights into Cardiac Recovery

“…Studies performed mostly with 1 st generation pulsatile LVADs suggest that mechanical unloading can result in improvement in myocardial structure and function, and some patients can be weaned from the mechanical support with sustained myocardial recovery (4)(5)(6)(7)(8)(9). However, the results of these studies on LVAD-induced reverse remodeling and cardiac recovery were variable and inconclusive for several reasons we have recently summarized (10): (1) small size of studies, (2) retrospective design of most studies, (3) non-standardized monitoring of heart function during LVAD support, (4) variations in the duration of LVAD unloading, (5) drugs concurrent to LVAD therapy varied and were not documented, (6) divergences in cardiac recovery criteria/LVAD weaning criteria and (7) diversity of the populations studied with respect to propensity for cardiac recovery (extent of pre-LVAD cardiac remodeling, HF etiology, inclusion of both acute and chronic HF patients, etc.). These issues have led to skepticism as to whether pulsatile LVAD-induced myocardial recovery is a 'real' and consistent phenomenon or an anecdotal experience (10,11).…”