Do Patients Supported With Continuous-flow Left Ventricular Assist Device Have a Sufficient Risk of Death to Justify a Priority Allocation? A Propensity Score Matched Analysis of Patients Listed in UNOS Status 2.

Background: Outcomes of continuous flow left ventricular assist devices (CF-LVADs) as bridge to transplant have significantly improved. The question has arisen whether patients on CF-LVADs have an increased risk of death on the waiting list as to justify a priority allocation (status 1). The aim of this study was to compare the survival after implantation of CF-LVADs with the survival on the waiting list for patients initially listed in United Network for Organ Sharing (UNOS) status 2.

Methods: All patients 18 years or older listed for heart transplantation (HT) in the United States between 2011 and 2013 in UNOS status 2 with no mechanical circulatory support at time of listing were analyzed. Patients were divided into 2 groups, depending on whether they received a new CF-LVAD while listed (CF-LVAD group) or not (NO-LVAD) and were further matched on their propensity score (PS) in a 1:2 ratio.

Results: Two hundred eighty-seven CF-LVAD patients were matched to 574 NO-LVAD patients. Survival after CF-LVAD was significantly lower at 24 months compared with waiting list (75.4 ± 4.4% vs 91.2 ± 8.9%, P < 0.0001). Further, survival was not significantly different between the 2 groups at 24 months after transplantation (81.3 ± 5.9% vs 86.7 ± 3.3%, P = 0.3).

Conclusions: Survival of patients listed in UNOS status 2 who receive a CF-LVAD while listed is significantly lower compared to patients who do not receive mechanical support on the waiting list. The current priority in the allocation system given to patients on CF-LVAD seems justified. Further posttransplant survival is not negatively influenced by previous CF-LVAD implantation.