Increased aortic augmentation index is associated with reduced exercise capacity after heart transplantation

OBJECTIVE: Exercise capacity is often reduced after heart transplantation. We aimed to investigate the association between aortic stiffness and exercise capacity after heart transplantation. METHODS: We retrospectively analyzed the data of patients who underwent a cardiopulmonary exercise test and central hemodynamic measurements over 1 year following heart transplantation, from Janary 2011 to June 2018. RESULTS: A total of 54 patients (mean age, 49 years; 72% men) were analyzed. The median peak oxygen uptake level was 21.1 ml/kg per min at a median time of 13 months after heart transplantation. In univariate linear regression, recipient age, pulmonary arterial pressure, pulmonary capillary wedge pressure, hemoglobin level, estimated glomerular filtration rate, aortic augmentation index, and pulse wave velocity were significant predictors for peak oxygen uptake level. After adjustment for other confounding variables, heart rate-corrected aortic augmentation index was a significant predictor for peak oxygen uptake (β = -0.141, 95% confidence interval, -0.263 to -0.058, P = 0.003). CONCLUSION: In the present study, increased aortic augmentation index was associated with reduced exercise capacity after heart transplantation. Therefore, this simple measurement of aortic stiffness should be periodically used for the evaluation of exercise capacity after heart transplantation.