Introduction
Orthotopic heart transplantation (OHT) remains the gold standard
treatment for advanced stage heart failure1. When
selecting an appropriate donor for each intended recipient, it is
paramount that donor-to-recipient sizing is within acceptable standards
in order to meet the cardiac output demands of its
recipient2,3. As a donor heart under consideration
typically cannot be directly inspected prior to the deployment of a
harvesting team, a number of different metrics have been utilized in
clinical practice as a quick tool for sizing. These metrics include
height, weight, and/or body mass index (BMI) ratios, and even predicted
heart mass (pHM) calculations2–6. For weight sizing,
some experts have advocated to finding a donor-recipient match pair with
≤ 30% weight discrepancy7, but others advocate for a
more conservative ≤ 20% discrepancy8,9. However, the
correlations with some of these measurements to actual heart size have
come into question.
In addition to choosing a donor heart of optimal size, considerations
must also be taken into donor and recipient gender. Prior study has
suggested that female to male (FtoM) donation may be associated with
increased risk of posttransplant mortality10–13. A
possible explanation is that a donor female graft may be more likely to
be under-sized when paired with a male recipient, resulting in a cardiac
supply-demand mismatch in the posttransplant period. As there is no
definitive consensus with regards to how donor-recipient heart sizing
should be conducted, we sought to analyze the distributions of sizing in
the FtoM OHT population using available sizing metrics. We aimed to
investigate the impacts of these metrics on posttransplant survival in
this potentially higher-risk transplant cohort.