The Association Between Preoperative Pectoralis Muscle Quantity and Outcomes After Cardiac Transplantation

Abstract

Background: Sarcopenia is underappreciated in advanced heart failure and is not routinely assessed. In patients receiving a left ventricular assist device (LVAD), preoperative sarcopenia, defined using CT-derived pectoralis muscle area index (muscle area indexed to body surface area), is an independent predictor of post-operative mortality. The association between preoperative sarcopenia and outcomes after heart transplant (HT) is unknown. Objectives: The primary aim was to determine if preoperative sarcopenia, diagnosed using pectoralis muscle area index, is an independent predictor of days alive and out of the hospital (DAOH) post-transplant. Methods: Patients who underwent HT from January 2018 to June 2022 with available preoperative chest CT scans were included. Sarcopenia was diagnosed as pectoralis muscle area index in the lowest sex-specific tertile. The primary endpoint was DAOH at 1-year post-transplant. Results: 169 patients were included. Patients with sarcopenia (n=55) had fewer DAOH compared to those without, with a median difference of 17 days (320 vs. 337 days, p=0.004). Patients with sarcopenia had a longer index hospitalization and were also more likely to be discharged to a facility other than home. In a Poisson regression model, sarcopenia was a significant univariable and the strongest multivariable predictor of DAOH at 1-year (Parameter estimate = -0.17, 95% CI -0.19 to -14, p = <0.0001). Conclusions: Preoperative sarcopenia, diagnosed using pectoralis muscle area index, is an independent predictor of poor outcomes after HT. This parameter is easily measurable from commonly obtained preoperative CT scans and may be considered in the transplant evaluation.