Typical structural features of the athlete`s heart as defined by echocardiography has been extensively described, however information concerning extracardiac structures as the inferior vena cava is scarce. 58 top level athletes and 30 healthy matched controls (age range 18-27) underwent a complete Doppler-echo study. Inferior vena cava (IVC) diameter was determined in the subxyphoid approach, 10-20 mm away from its junction to the right atrium. Measures reflect the median values between maximal inspiratory and expiratory values. IVC respiratory collapsibility index was determined as well. IVC in athletes was 2.31 ± 0.46 cm compared to 1.14 ± 0.13 cm in controls (p < 0.001). Swimmers had an IVC diameter of 2.66 ± 0.48cm compared to 2.17 ± 0.41 cm in other athletes (p < 0.05). IVC was normal (<1.7cm) in 5.2 %, dilated (1.7-2.5 cm) in 70.7% and very dilated (³ 2.6 cm) in 24.1% of athletes. Collapsibility index was 58 ± 6.4 % in athletes compared to 70.2 ± 4.9 % in controls (p<0.001). Correlation was found between IVC and VO2 max (r = 0.81, p < 0.001) and right ventricle (r= 0.81, p < 0.001) and with the collapsibility index (r= ­ 0.57, p<0.05). Multiple regression analysis showed impact of VO2 max, cardiac output, right ventricular & left ventricular end-diastolic dimensions on IVC diameter. IVC dilatation probably represents adaptation of an extracardiac structure to chronic strenuous exercise in top level, elite athletes.
© Copyright 1999 5th IOC World Congress on Sport Sciences with the Annual Conference of Science and Medicine in Sport 1999. All rights reserved.