Differences in wait-list mortality: Temporary vs durable circulatory support devices.

Area of Science:

• Cardiology
• Transplantation Medicine
• Medical Devices

Background:

• Changes in the United Network for Organ Sharing (UNOS) allocation system in 2018 influenced the use of durable left ventricular assist devices (LVADs) versus temporary mechanical circulatory support (MCS) as a bridge to heart transplantation.
• This shift necessitated a comparative analysis of patient outcomes between these two support strategies.

Purpose of the Study:

• To compare the composite outcome of waitlist mortality and delisting incidence at one year between patients supported by durable LVADs and temporary MCS.
• To evaluate the effectiveness of different mechanical circulatory support devices in the context of updated organ allocation policies.

Main Methods:

• A cohort study included adult patients listed for heart transplantation on mechanical circulatory support between October 2018 and October 2021.
• Exclusion criteria included patients with right ventricular devices, biventricular devices, total artificial hearts, and extracorporeal membrane oxygenators.
• Propensity-score matching was used to compare outcomes between durable LVAD and temporary MCS groups, with survival analysis employing Kaplan-Meier curves and Cox regression.

Main Results:

• The study analyzed 4,569 patients (1,877 temporary MCS, 2,692 durable LVADs), with 660 patients included after propensity-score matching.
• The composite event rate was significantly lower in the durable LVAD group (15.9%) compared to the temporary MCS group (35.2%) (p < 0.001).
• Temporary MCS was associated with a significantly higher hazard ratio (HR) for adverse outcomes (HR 3.37, p < 0.001), with the HeartMate 3 (HM3) device showing the best outcomes.

Conclusions:

• In a propensity-score-matched analysis, durable mechanical circulatory support demonstrated superior outcomes compared to temporary mechanical circulatory support for patients awaiting heart transplantation.
• The HeartMate 3 device was associated with the lowest risk of composite adverse outcomes, highlighting its efficacy in this patient population.