COMPARISON OF ATHLETES WITH LIFE-THREATENING VENTRICULAR ARRHYTHMIAS WITH 2 GROUPS OF HEALTHY ATHLETES AND A GROUP OF NORMAL CONTROL SUBJECTS

Sudden cardiac death in well trained athletes is most often superimpos ed on the presence of structural heart disease. However, some athletes die suddenly in the absence of overt heart disease. To improve identi fication of athletes at high risk for ventricular tachycardia (VT), ve ntricular repolarization, the signal-averaged electrocardiogram (ECO), and the echocardiogram from 13 male athletes with symptomatic VT and with out evidence of manifest cardiac disease were compared with data obtained in 3 matched control groups (15 apparently healthy profession al road cyclists, 10 professional basketball players, and 15 normal co ntrol subjects without any sports activity). All patients had apparent ly normal QRS duration on the routine ECG, and none were taking antiar rhythmic drugs. Echocardiography and signal-averaged electrocardiograp hy were useful in distinguishing the group of athletes with tachyarrhy thmias from the group of normal nonsporting controls, but not from bot h groups of normal athletes. The QT interval (V-4) and the QT interval corrected with the cubic root were shorter for the nonsporting contro ls. Three parameters for QT dispersion showed significant differences (p < 0.003) between athletes with disease and all other groups. It is concluded that although significant differences were detected between normal subjects and the 3 groups of athletes by routine ECG, the signa l-averaged ECC, and echocardiography, only an increased QT dispersion from the 12-lead ECG was helpful in distinguishing athletes with VT fr om other athletes.