Body composition and maximal exercise capacity after heart transplantation

Aims Maximal exercise capacity as measured by peak oxygen consumption (pVO2) in cardiopulmonary exercise testing (CPET) of heart transplant recipients (HTR) is limited to a 50–70% level of healthy age‐matched controls. This study investigated the relationship between body composition and pVO2 during the first decade post‐transplant. Methods and results Body composition was determined by dual‐energy X‐ray absorptiometry (DXA) and pVO2 by CPET in 48 HTR (n = 38 males; mean age 51 ± 12 years). A total of 95 assessments were acquired 1–9 years post‐transplant, and the results of four consecutive periods were compared [Period 1: 1–2 years (n = 25); 2: 3–4 years (n = 23); 3: 5–6 years (n = 23); 4: 7–9 years (n = 24)]. Linear regression analysis analysed the correlation between pVO2 and pairs of appendicular lean mass (ALM) and fat mass (FM). The relation between ALM and daily dose of calcineurin inhibitor (CNI) was explored using partial correlation controlling for age, gender, and height. pVO2 increased from 0.98 (0.34) to 1.35 (0.35) L/min (P 8.8 kg/m2). ALM normalized to body mass index increased from 0.690 (0.188) to 0.848 (0.204) m2 (P = 0.02) between Periods 1 and 4, explaining 45% of the variance of pVO2 (R 2 = 0.455; P