Mechanical Circulatory Support as a Bridge-to-Transplant Candidacy: When Does It Work?

Durable mechanical circulatory support (dMCS) devices can be offered as a bridge-to-transplant (BTT) or as a bridge-to-candidacy (BTC) strategy for candidates with contraindications to transplant listing, including pulmonary hypertension (BTC-PH), morbid obesity (BTC-Obes), social issues (BTC-Soc), or chronic illness (BTC-Illness). An understanding of the trajectory of BTC patients could guide future triage of advanced heart failure patients who are not candidates for transplantation. We performed a retrospective review all patients who underwent dMCS implantation as either BTT (206 patients) or BTC (114 patients) at our center from January 1, 2010, to March 31, 2020. There was no significant difference in mortality between BTC patients and BTT patients. Compared with the BTT group, significantly more patients in the BTC-PH group were transplanted (81% vs. 63%; p < 0.05) and significantly fewer patients in the BTC-Obes group (44%; p < 0.05) and BTC-Soc group (39%; p < 0.05) were transplanted. Additionally, the readmission rate was higher for those in the BTC-Obes (6.2 vs. 2.1; p < 0.05) and BTC-Soc (3.9 vs. 2.1; p < 0.05) groups. Bridge-to-candidacy patients generally had poorer post-dMCS trajectories than BTT patients. Centers should not be dissuaded from pursuing a BTC strategy for qualified patients; however, careful consideration of potential adverse outcomes is necessary.

Impact of the United Network for organ sharing 2018 donor heart allocation system on transplant morbidity and mortality.

BACKGROUND: While the revised UNOS HTx donor allocation system aimed to minimize waitlist mortality by prioritizing more critically ill transplant candidates, there is concern for increased post-transplant morbidity and mortality. We examined the impact of the revised allocation system on waitlist and post-transplant outcomes at a high-volume transplant center. METHODS: One hundred and sixty nine adult patients underwent first-time single-organ HTx one year before (Era 1:79 patients) and after (Era 2:90 patients) implementation of the new allocation system (10/18/2018). Clinical characteristics, waitlist outcomes, and post-transplant morbidity and mortality were compared. RESULTS: Era 2 patients were twice as likely to be transplanted on temporary mechanical circulatory support (43% vs. 19%, p < .0001). While Era 2 waitlist time was shorter (10 vs. 43 days, p < .001), exception status requests (21.1% vs. 17.9%) and waitlist mortality (3.3% vs. 2.2%) were similar. There was no difference in primary graft dysfunction, intensive care unit or hospital length of stay, readmissions, rejection, allograft vasculopathy, or 1-year survival (91.1% vs. 93.7%). CONCLUSIONS: In a high-volume center, the revised HTx allocation system shortened waitlist time with no significant change in waitlist mortality or observed impact on post-transplant outcomes. With careful patient selection, the revised allocation system may optimize waitlist and post-transplant outcomes.