Sex differences in submaximal exercise tests correlation with coronary cineangiography in 133 patients.

Submaximal treadmill exercise testing up to 80 percent of the maximal heart rate predicted for age was performed on 138 normal men and 142 normal women. Sex difference was analyzed in terms of 3 ST-T items: J, midpoint between J and the peak of T (mid-ST), and the peak of T in leads II, V4 and V. at rest and after exercise. A greater mid-ST point depression at rest, during and after exercise was found in normal women than in men (p< 0.001). Sex-adjusted 95% confidence . limits were estimated. Using these norms, similar evaluations were carried out on 133 patients who were being evaluated for possible coronary insufficiency, eighty-four (64 men and 20 women) of whom had significant angiographic disease (:2. 75% narrowing) and forty-nine (26 men and 23 women) of whom had not. The most sensitive and specific correlate with anatomic coronary disease was the absolute change in mid-ST point. Using criteria developed in the normal group, sensitivity for angiographic positives was 70.3% (45 of 64) in men and 70.0% (14 of 20) in women (P =not statistically significant); specificity was 92.3% (24 of 26) in men and 87.0% (20 of 23) in women (P = not statistically significant). When these male standards were used in female patients, there was a decrease in specificity from 87.0% to 43.5% (P< 0.001). Sex-adjusted standards render the ECG exercise test as effective a diagnostic tool in women as in men.