Survival After Orthotopic Heart Transplantation in Patients Undergoing Bridge to Transplantation With the HeartWare HVAD Versus the Heartmate II

Background: Our objective was to determine whether the choice of a HeartWare HVAD as opposed to a Heartmate II left ventricular assist device (HMII LVAD), impacts survival after heart transplantation after controlling for patient, donor, and center characteristics.

Methods: We queried the United Network for Organ Sharing (UNOS) database, which has recently made pretransplantation device duration available, for all adult patients undergoing bridge to transplantation (BTT) between January 2011 and March 2016. Recipient, donor, and transplant-specific characteristics were compared between patients receiving either device. Unadjusted survival was estimated with the Kaplan-Meier method. Risk-adjusted Cox proportional hazard models were constructed to determine the independent impact of device selection on mortality.

Results: Three thousand three hundred fifty-six patients who received the HMII and 1,051 patients who received the HVAD met inclusion criteria. Patients who received the HMII had a longer mean duration of VAD support (HMII, 429 days versus HVAD, 314 days; p < 0.001) but spent shorter periods on the waiting list (median, 190 days versus 232 days; p < 0.001). Patients who received the HMII had worse pre-LVAD renal function than did those who received the HVAD (glomerular filtration rate [GFR], 57 mL/min versus 62 mL/min, respectively; p = 0.001), but there was no difference in postoperative new-onset dialysis after transplantation (11.6% versus 10.5%, respectively; p = 0.14). There was no difference in unadjusted posttransplantation 30-day (95.5% versus 96.7%, respectively; log-rank p = 0.09), 6-month (91.8% versus 92.6%, respectively; p = 0.35), or 1-year (89.7% versus 90.9%, respectively; p = 0.22) survival between the 2 groups. After risk adjustment with Cox modeling, device selection did not predict mortality at any time point.

Conclusions: Among patients who received a BTT LVAD and then received a heart transplant, no survival differences were seen between patients initially implanted with an HVAD versus an HMII.