Predicted Heart Mass (PHM) Ratio for Size Matching in Heart Transplant Post LVAD.

Recent studies point towards donor/recipient predicted heart mass (PHM) ratio as an emerging metric for size matching. Our study examines if PHM ratio is a better marker than weight ratios in size matching for heart transplant, specifically in post LVAD patient population. 11,891 patients with LVAD who received heart transplants between the years 1997 to 2020 in the Scientific Registry of Transplant Recipient's database were analyzed. We compared 5 size match metrics including Donor/recipient ratios of weight, height, BMI, BSA and PHM. We divided each metric into 3 equally sized groups. Univariate and multivariate cox proportional hazard models for one year mortality was calculated. On multivariate analysis, patients in the undersized group with PHM ratios of less than 0.82 had hazards ratio of 1.3 (95% CI, 1.08-1.6; p-0.001), suggestive of increased mortality in post LVAD patients. There was no difference in one year survival between matched (PHM ratio 0.82-1.2) and oversized group (PHM ratio>1.2). Under-sizing or oversizing based on other metrics of weight, BMI, BSA or height were not predictive of outcomes at one year. Donor/recipient PHM ratio is emerging as a better metric in size matching in heart transplant than weight ratios. When size matching for heart transplant post LVAD, PHM ratio < 0.82 confers higher mortality within a year post transplant. Oversizing of PHM >1.2 does not afford any advantage in heart transplant post LVAD. [ABSTRACT FROM AUTHOR]