Exercise blood pressure changes and aortic dilatation in male Masters endurance athletes

With aging, aortic dilatation represents a primary risk factor for acute aortic syndromes.1 Among endurance-trained Masters athletes, clinically relevant aortic dilatation, defined by a diameter at the aortic root (AR) or ascending aorta ≥40 mm, is also common.2 Whether this phenotype represents adaptive vascular remodelling, akin to the ‘athlete’s heart’, vs. a manifestation of overuse pathology is uncertain. We sought to analyse the association between changes in exercise blood pressure (BP) and AR size in a cross-sectional cohort of male Masters endurance athletes. We hypothesized that an increased systolic BP (SBP) response to exercise would be associated with larger AR size. Subjects were taken from a developing registry of healthy Masters endurance athletes recruited from the Atlanta Track Club (Atlanta, GA, USA), a regional running organization, created to study cardiovascular risk in Masters athletes. Fasting blood work and maximal-effort treadmill cardiopulmonary exercise testing (CPET) were obtained on all athletes. Exercise history was self-reported and estimated as weekly metabolic equivalents of task (MET).3 Athletes without established diabetes, hypertension, or coronary artery disease and normal resting and exercise ECG proceeded with trans-thoracic echocardiography and vascular applanation tonometry [carotid-femoral pulse wave velocity (PWV), SphygmoCor, Atcor Medical].