Assessment of the exercise electrocardiogram in women versus men using tomographic myocardial perfusion imaging as the reference standard.

The exercise electrocardiogram (ECG) is widely believed to be less accurate in women, primarily due to a high prevalence of false-positive tests. The purpose of this study was to examine the relative accuracy of the exercise ECG in women versus men in 8,671 patients (3,213 women, 5,458 men) using myocardial perfusion imaging as the reference standard. More women (14%) than men (10%) had a false-positive ECG (p <0.001), but the absolute difference was relatively small. The false-negative rate was considerably lower in women (17% vs 32%, p <0.001). Compared with men, women had lower test sensitivity (30% vs 42%, p <0.001) and positive predictive value (34% vs 70%, p <0.001) but higher specificity (82% vs 78%, p = 0.002), negative predictive value (78% vs 52%, p <0.001), and accuracy (69% vs 58%, p <0.001). In patients with a false-negative exercise ECG, "high-risk" scans were less prevalent in women (12% vs 19%, p <0.001). In the smaller subset of patients referred for coronary angiography (205 women, 838 men), the false-positive electrocardiographic rate was again higher in women (13% vs 7%, p = 0.003), but neither specificity (69% vs 74%, p = NS) nor accuracy (60% vs 66%, p = NS) was different between the sexes. Thus, the percentage of patients with a false-positive exercise ECG was higher in women than men but low in absolute terms (<15%) for both sexes. Test specificity was not lower in women. These results suggest that gender should not be a major determinant for selecting stress imaging over standard treadmill testing.

Sex differences in left ventricular geometry in aortic stenosis: impact on outcome.

OBJECTIVE: This study of surgical aortic stenosis characterized sex differences in left ventricular (LV) geometry and outcome. MATERIALS AND METHODS: We examined 92 women and 82 men who underwent echocardiography before valve replacement for aortic stenosis. RESULTS: Women had a smaller cavity size (LV end-diastolic diameter 48.2 +/- 7 mm in women vs 53.6 +/- 7.6 mm in men; p = 0.0001) and higher ejection fraction (59% in women vs 54% in men; p = 0.02). LV mass was greater in men than women (300.4 +/- 88 g in men vs 250.6 +/- 85.8 g in women; p = 0.0055) but when corrected for body surface area, the difference was not significant. The prevalence of LV hypertrophy was similar in both sexes (51% in women vs 49% in men; p = 0.62). The 5-year survival was 82% in women and 79% in men (p = 0. 9). CONCLUSION: Several descriptors of LV geometry differed between men and women. These differences were largely eliminated after normalizing for body surface area. No differences in surgical mortality or long-term outcome were noted.