Perioperative Pectoralis Muscle Mass and Attenuation Estimated by Computed Tomography are Not Predictors for Mortality after Heart Transplantation

Abstract

Purpose End-stage heart failure (HF) is often associated with malnutrition and sarcopenia, both of them are related to adverse HF outcomes. Skeletal muscle mass and attenuation are predictors of mortality after continuous flow left ventricular devices (LVAD) implantation. Our purpose was to assess the prognostic impact of skeletal muscle mass on patients undergoing heart transplantation (HT). Methods Retrospective study of a single-center HT population, between 2009 and 2019. Patients > 18 years-old with a computed chest scan in the previous 6 months before HT were included. Multiorgan transplants were excluded. Unilateral pectoralis muscle mass indexed (PMMi) to body surface area and attenuation (by mean Hounsfield units [PHUm]) were measured in each patient. HT patients were classifiedin tertiles according to PMMi and PHUm and characteristics of patients were compared by Chi-square, t-student and Kruskall-Wallis. Multivariate Cox regression analyses were performed to assess the impact of preoperative PMMi and PHUm on survival after HT. Results 132 patients were included, mean age 58.9, 16.7% female, median follow-up 3.67 years (interquartile range 1.7-5.9 years). 41.7% of patients underwent urgent HT (1.5% INTERMACS 1 situation, 15.2% INTERMACS 2 and 28% INTERMACS 3). Both PMMi and PHUm were lower in females and for lowest weight recipients. Urgent HT frequency was similar between tertiles of PMMi, but recipients in the higher tertile of PHUm were more frequently transplanted in an urgent status (38.2% vs 21.8% in the lowest tertile, p= 0.029). 26 patients (19.7%) died during follow-up, 12 (9.1% of total cohort) during HT admission. In the Cox regression analyses, neither PMMi (HR 1.034, 95% CI 0.891-1.2, p= 0.659) nor PHUm (HR 1.02, 95% CI 0.992-1.050, p=0.160) were associated with an increased mortality. Only the needed of mechanical circulatory support and hemofiltration after HT were associated with a higher risk of death. Conclusion Among this single-center HT recipients population, neither lower PMMi nor lower PHUm were associated with worse outcomes after HT.