Mechanical circulatory support pathways that maximize post-heart transplant survival

Heart transplant (HTx) recipients reach transplantation through increasing numbers of support pathways, including transition from one pathway to another. Outcomes of patients successfully bridged with various support pathways are unknown. We sought to identify mechanical circulatory support pathways that maximize survival after HTx.

A supplemented United Network Organ Sharing Dataset tracked status 1 HTx outcomes from 2000 to 2010. Recipients were grouped based on support pathway before HTx, including those transitioning from one pathway to another. Multivariable factors for time-related death were sought using Cox proportional hazard regression models.

We identified 13,250 status 1 HTx recipients. Initial support pathways were inotropes (n = 7,607), left ventricular assist device (LVAD [n = 4,034]), intraaortic balloon pump (n = 729), biventricular assist device (n = 521), extracorporeal membrane oxygenation (ECMO [n = 316]), and right ventricular assist device (n = 43). Multivariable analysis demonstrated that LVAD use conferred a survival advantage (hazard ratio [HR] 0.71; p < 0.001), whereas all other support pathways, including inotropes (HR 1.1; p = 0.02), right ventricular assist device (HR 1.9; p = 0.01), and ECMO (HR 2.2; p < 0.001) increased the risk of post-HTx death. Support pathway transition (both escalation and reduction) occurred in 2,175 patients. Patients who transitioned from either ECMO or biventricular assist device support at listing to LVAD-only support at HTx had improved post-HTx survival that was comparable to patients who had LVAD-only therapy throughout their course (p = 0.74).

The LVAD supported HTx recipients have better posttransplant survival than patients after all other mechanical support pathways. Survival after HTx is optimized when ECMO or biventricular assist device support can be transitioned to LVAD-only support. Our findings should aid clinical decision making and inform organ allocation policy development intended to maximize societal benefits of HTx.