Prevalence and clinical significance of aortic root dilation in highly trained competitive athletes

Abstract

Background: Few data are available that address the impact of athletic training on aortic root size. We investigated the distribution, determinants, and clinical significance of aortic root dimension in a large population of highly trained athletes. Methods and Results: Transverse aortic dimensions were assessed in 2317 athletes (56% male), free of cardiovascular disease, aged 24.8±6.1 (range, 9 to 59) years, engaged in 28 sports disciplines (28% participated in Olympic Games). In males, aortic root was 32.2±2.7 mm (range, 23 to 44; 99th percentile=40 mm); in females, aortic root was 27.5±2.6 mm (range, 20 to 36; 99th percentile=34 mm). Aortic root was enlarged ≥40 mm in 17 male (1.3%) and ≥34 mm in 10 female (0.9%) subjects. Over an 8-year follow-up period, aortic dimension increased in these male athletes (40.9±1.3 to 42.9±3.6 mm; P<0.01) and dilated substantially (to 50, 50, and 48 mm) in 3, after 15 to 17 years of follow-up, in the absence of systemic disease. Aortic root did not increase significantly (34.9±0.9 to 35.4±2.1 mm; P=0.11) in female athletes. Multiple regression and covariance analysis showed that aortic dimension was largely explained by weight, height, left ventricular mass, and age (R=0.63; P<0.001), with type of sports training having a significant but lower impact (P<0.003). Conclusions-: An aortic root dimension >40 mm in highly conditioned male athletes (and >34 mm in female athletes) is uncommon, is unlikely to represent the physiological consequence of exercise training, and is most likely an expression of a pathological condition, mandating close clinical surveillance. © 2010 American Heart Association, Inc.