Electrocardiographic findings in female endurance athletes.

OBJECTIVE

To determine the prevalence of aberrations in the resting electrocardiogram (ECG) in female athletes.

DESIGN

Case-control study.

PARTICIPANTS

Thirty female endurance athletes and 30 age-matched nonobese nonathletic control subjects.

MAIN OUTCOME MEASURES

Different measurements based on resting ECGs.

MAIN RESULTS

The athletes had lower heart rate (mean 53 +/- SD 7) than the controls (67 +/- 11; p < 0.0001), but no group difference was found in atrioventricular conduction (PQ interval). Cornell voltage (RaVl + SV3) reflecting left ventricular mass was higher in athletes (1.18 +/- 0.58 mV vs. 0.78 +/- 0.41 mV; p = 0.0030), but the deviations from normal limits were small. The index reflecting right ventricular mass (RV1 + SV5) was higher in athletes (0.58 +/- 0.23 mV) than controls (0.45 +/- 0.23 mV; P = 0.036) but did not exceed the criterion for right side hypertrophy. QRS duration was slightly prolonged in athletes (99 +/- 10 ms vs. 92 +/- 9 ms; p = 0.010), as were rate-adjusted QT intervals (p < 0.05). J-point elevations (p = 0.0062) and ST-segment elevations (p = 0.013) were seen more frequently in athletes, but were usually small.

CONCLUSIONS

The female athlete's ECG differs less from control subjects than has been reported in male athletes. Extrathoracal anatomic considerations may explain some of the sex differences. However, when clear-cut ECG abnormalities are observed in female athletes, organic heart disease must be carefully excluded.