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Updated: Mar 20, 2026
Author Spotlight: Enhancing Graft Viability Assessment Through Quantitative Metrics and Innovative Reservoir Systems
Published on: August 2, 2024
Donor Oversizing Results in Improved Survival in Patients with Left Ventricular Assist Device
Erin M Schumer1, Matthew C Black, Michael P Rogers
1From the *Department of Cardiovascular and Thoracic Surgery, and †Division of Cardiovascular Medicine, University of Louisville, Louisville, Kentucky.
Insights
For heart transplants, using an oversized donor organ improves graft survival in patients with a left ventricular assist device (LVAD). Donor-recipient BMI ratio is key for long-term success in LVAD patients.
Area of Science:
- Cardiology
- Transplantation Medicine
- Biomedical Engineering
Background:
- Graft survival after heart transplantation is crucial for patient outcomes.
- Donor-recipient size mismatch, particularly donor undersizing, can negatively impact graft longevity.
- Left ventricular assist devices (LVADs) are increasingly used as bridge-to-transplant therapy.
Purpose of the Study:
- To investigate the impact of donor-to-recipient body mass index (BMI) ratio on heart transplant graft survival.
- To determine if LVAD support at the time of transplant modifies the effect of donor-recipient size mismatch.
- To identify optimal donor organ sizing strategies for heart transplant recipients, especially those with LVADs.
Main Methods:
- Retrospective analysis of the United Network for Organ Sharing database (2008-2013).
- Inclusion of adult patients undergoing heart transplantation, stratified by LVAD status.
- Categorization into donor:recipient BMI ratio groups: <0.8 (undersized), 0.8-1.2 (matched), and >1.2 (oversized).
- Kaplan-Meier and Cox regression analyses for graft survival and influencing factors.
Main Results:
- No significant difference in graft survival based on BMI ratio in patients without LVADs (p=0.634).
- Significantly worse graft survival in undersized (BMI ratio <0.8) patients with LVADs compared to matched or oversized groups (p=0.032).
- Cox regression identified age, creatinine, waitlist time, UNOS status, BMI ratio, and bilirubin as significant factors affecting graft survival.
Conclusions:
- An oversized donor organ (BMI ratio >1.2) is associated with significantly improved long-term graft survival for heart transplant recipients with LVAD support.
- Consideration of an oversized donor organ is recommended for patients supported by an LVAD awaiting heart transplantation.
- Donor-recipient size matching, favoring larger donor organs for LVAD patients, is a critical factor for optimizing heart transplant outcomes.
Abstract:
Donor to recipient undersizing can result in diminished graft survival. The United Network for Organ Sharing database was retrospectively queried from January 2008 to December 2013 to identify adult patients who underwent heart transplantation. This population was divided into those without and with a left ventricular assist device (LVAD) at the time of transplant. Both groups were further subdivided into three groups: donor:recipient body mass index (BMI) ratio <0.8 (undersized), ≥0.8 and ≤1.2 (matched), and >1.2 (oversized). Kaplan-Meier analysis was used to compare graft survival. Cox regression analysis was used to identify factors affecting graft survival time. There was no difference in mean graft survival between undersized, matched, and oversized groups in patients without an LVAD (p = 0.634). Mean graft survival was significantly worse for undersized patients with an LVAD when compared with matched and oversized patients (p = 0.032). Cox regression revealed age, creatinine, waitlist time, United Network for Organ Sharing status, BMI ratio, and total bilirubin as significant factors affecting graft survival time. A donor to recipient BMI ratio of ≥1.2 results in significantly improved long-term graft survival for patients with an LVAD at the time of heart transplantation compared with patients with a BMI ratio of <1.2. An oversized organ should be considered for patients supported with an LVAD.
