Myocardial recovery evaluation from ventricular assist device in patients with dilated cardiomyopathy

Abstract

Aims: The removal of left ventricular assist device (LVAD) after myocardial recovery can provide survival benefits with freedom from LVAD-associated complications. However, in the absence of standardization, the weaning evaluation and surgical strategy differ widely among centres. Therefore, we analysed the experiences of LVAD explantation with our protocol in dilated cardiomyopathy (DCM) patients and investigated the validity of our weaning evaluation and surgical strategy from the perspective of optimal long-term survival.

Methods and results: All LVAD explantation patients in our institution between May 2012 and May 2020 were enrolled. All patients were evaluated by our three-phase weaning assessment: (i) clinical stability with improved cardiac function under LVAD support; (ii) haemodynamic stability shown by ramp-loading and saline-loading test; (iii) intraoperative pump-off test. Explant surgery involved removal of the whole system including driveline, pump, sewing ring and outflow-graft, and closure of an apical hole. Intra-operative, peri-operative, and post-operative outcomes, including all-cause mortality and LVAD associated major complications, were retrospectively analysed. A total of 12 DCM patients (DuraHeart, n = 2; EVAHEART, n = 2; HeartMate II, n = 6; HeartMate 3, n = 2) had myocardial recovery after a median 10 months [interquartile range (IQR); 6.3-15 months] support and qualified for our LVAD explantation study protocol [median age: 37 y, IQR; 34-41 years; 83% men]. The median left ventricular ejection fraction was 20% (IQR; 12-23%) at LVAD-implantation and 54% (IQR: 45-55%) before LVAD explantation (P < 0.001). There were no perioperative complications and median ICU stay was 4 days (IQR; 2-4 days). All patients were discharged after a median of 24 days (IQR: 17-28 days) postoperatively. No patient suffered from any cardiac event (heart failure hospitalization, re-implantation of LVAD, or heart transplantation) at a median of 40 months (IQR: 17-58 months) follow up. All patients are alive with NYHA functional class 1 with preserved left ventricular function.

Conclusions: The evaluation of LVAD explant candidates by our weaning protocol was safe and effective. In the patients completing our protocol successfully, LVAD explantation is feasible and an excellent long-term cardiac event free-survival seems to be achieved.

Keywords: Heart failure; LVAD explantation; Left ventricular assist device; Mechanical circulatory support; Weaning protocol.

Figure 1

Weaning protocol sequence. BNP, brain natriuretic peptide; CI, cardiac index; CVP, central venous pressure; LVAD, left ventricular assist device; LVDd, left ventricular diastolic diameter; mPCWP, mean pulmonary capillary wedge pressure; mRAP, mean right atrium pressure; NYHA, New York Heart Association; PAP, pulmonary artery pressure; SvO₂, mixed venous oxygen saturation.

Figure 2

Overall survival after LVAD explantation. Kaplan–Meier curves for freedom from al cause mortality, showing 100% survival rate at 1 year after LVAD explantation. All patient survived at median 3 years (IQR; 1–4 years) follow‐up.