Noninvasive evaluation of ventricular hypertrophy in professional athletes

Abstract

Athletes often exhibit ECG findings which are considered to be abnormal. Therefore, the authors used noninvasive graphic methods to study 42 active professional male basketball players ranging in age from 21 to 31 years, without clinically evident heart disease. Of the 42, 11 (25%) met the Romhilt Estes ECG voltage criteria for left ventricular hypertrophy, and 12 (29%) satisfied VCG criteria for left ventricular enlargement; nine (21%) had left ventricular hypertrophy by both methods. In 33 subjects (79%) the 0.04 sec vector in the horizontal plane was anterior, and 29 of these exhibited one or more standard criteria for right ventricular hypertrophy by ECG, while 18 satisfied VCG criteria for right ventricular enlargement; the ECG and VCG were concordant for right ventricular hypertrophy in 16 subjects (38%). Submaximal treadmill exercise tests (Bruce protocol) were normal in eight athletes, while in one subject ventricular premature beats occurred during the test. In 24 of 25 athletes (96%) from whom phonocardiograms were obtained a third heart sound was recorded, while in 14 (56%), a fourth heart sound was present. Of the 14 athletes who had a fourth heart sound, 12 (86%) had either ECG or VCG evidence of ventricular hypertrophy. Only four of 23 athletes had an increased cardiothoracic ration (> .50) on routine chest X ray. Ten athletes and ten control subjects matched for height, weight and body surface area had echocardiograms satisfactory for analysis. The left ventricular end diastolic dimension in the athletes averaged 53.7 ± 1.3 (SE) mm compared with a value of 49.9 ± 0.7 mm in the control subjects (P<0.02), and was increased (≥56 mm) in four. Left ventricular posterior wall thickness averaged 11.1 ± 0.6 mm, compared with a value of 9.8 ± 0.5 mm in the control subjects (P<0.05), and was increased (≥11 mm) in six athletes. The right ventricular end diastolic dimension averaged 20.8 ± 1.1 mm compared with a value of 12.9 ± 2.2 mm in the controls (P<0.004), and was increased (≥23 mm) in four athletes. No athlete or control subject exhibited paradoxical septal motion. In athletes, ejection fraction (cube method) averaged 79 ± 2.0% and mean Vcf averaged 1.13 ± 0.04 circ/sec; these values did not differ from those of the control subjects. Thus, both right and left ventricular enlargement ('physiological hypertrophy') are often present in the well trained athlete, but left ventricular performance remains normal in the basal state in such individuals. The authors conclude that these individuals represent a selected subgroup of subjects who are variants of normal.