Triage of patients referred with advanced heart failure (HF) continues to revive the classic question: can we conduct a randomized trial comparing heart transplantation with durable left ventricular assist devices (LVADs)? Survival with the HeartMate III has improved, exceeding ∼80% at 2 years and approaching 60% at 5 years, often with good quality of life—results that appear similar to those observed at 2 and 5 years after heart transplantation.¹ What results would we anticipate from a trial that compares replacement of failing hearts using donated human hearts requiring immunosuppression with the implantation of LVADs to support failing hearts that remain in place? Although such answers would be welcome, conducting such a randomized trial poses formidable challenges. The scarcity of human donor hearts drives rationing down to a small number of selected candidates. Recent years have each begun with about 3000 patients already listed, such that there about 8000 patients waiting on the list at some time during the year. In 2023, about 5000 adults were added to the heart-waiting list, of whom about 4000 underwent transplantation. Allocation is prioritized according to the most urgent need, with over two-thirds of transplant recipients critically ill in status 1 or 2, most on temporary mechanical support (2023 Organ Procurement and Transplantation Network/Scientific Registry of Transplant Recipients (OPTN/SRTR Annual Data Report).

To perform the trial above, dynamic changes in transplant prioritization would disrupt randomization to transplantation, whereas LVADs could be implanted immediately from an effectively unlimited supply. Furthermore, donor scarcity would constrain translation of trial results into practice unless transplantations were found to be inferior to LVAD therapy. Our current experiences with LVADs as well as transplantations continue to be dominated by patients in critical condition.¹ However, the population most likely to gain from revised triage is, instead, the many “less sick” ambulatory patients typical of heart allocation status 6 and INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support) profiles 4–6.