Three-Year Left Ventricular Assist Device Outcomes and Strategy After Heart Transplant Allocation Score Change

Area of Science:

• Cardiology
• Transplantation Medicine
• Medical Policy

Background:

• The United Network for Organ Sharing (UNOS) updated heart allocation criteria in October 2018 to address evolving candidate mortality risks.
• Left ventricular assist device (LVAD) use has increased as a bridge to heart transplantation.
• Understanding the impact of policy changes on mechanical circulatory support device strategies is crucial.

Purpose of the Study:

• To evaluate the effect of the 2018 UNOS heart allocation score revision on LVAD implantation rates.
• To assess changes in the utilization of temporary mechanical circulatory support (MCS) devices post-policy change.
• To compare post-transplant outcomes between patients listed before and after the policy update.

Main Methods:

• Utilized the UNOS registry to identify adult first-time heart recipients with LVAD support at listing or transplant between January 2016 and March 2020.
• Categorized patients into "before" and "after" groups based on the October 18, 2018 policy change date.
• Analyzed demographics, clinical parameters, and survival data (collected through March 2023) using Kaplan-Meier curves and log-rank tests.

Main Results:

• Identified 4,387 recipients: 3,606 before and 781 after the score change.
• The "after" group showed a significant decrease in LVAD implantation (20.4% vs. 34.9%) but increased use of temporary MCS (e.g., ECMO, inotropes).
• The "after" group had longer travel distances to transplant centers and shorter waitlist times, with comparable 3-year survival rates.

Conclusions:

• The 2018 UNOS allocation score revision significantly altered mechanical circulatory support device strategies.
• A decrease in LVAD implantation was observed, accompanied by a rise in temporary MCS device utilization.
• Despite strategic shifts in MCS support, 3-year post-transplant survival remained consistent between the two eras.