Noninvasive assessment of T-wave abnormalities on precordial electrocardiograms in middle-aged professional bicyclists.

Six middle-aged, active, professional bicyclists with T-wave abnormalities on precordial ECGs were studied noninvasively. Twenty-five aged-matched bicyclists without T-wave abnormalities served as the control subjects. Increased voltage of SV1 + RV5 was demonstrated in all subjects. A 5-year follow-up study revealed that these abnormalities of T-wave inversion became more pronounced with age, except in one case. VCGs showed enlargement of anterior QRS loop and discordant T loop, in all cases. On echocardiography, thickness of both the interventricular septum and the left ventricular posterior wall, and left ventricular mass were significantly increased compared with the control group. 201Tl myocardial scintigraphy at rest and during exercise revealed no regional perfusion defects of the tracer in either case. We conclude that: (1) T-wave abnormalities of precordial ECGs in six middle-aged athletes were progressive in nature; and (2) these electrocardiographic abnormalities seem to be related to left ventricular hypertrophy induced by steady and strenuous training rather than to coronary artery disease.