Prognostic value of stress echocardiography in women with high (>= 80%) probability of coronary artery disease

Objective-To assess the prognostic significance of stress echocardiography in women with a high probability of coronary artery disease (CAD). Setting-Secondary and tertiary cardiology unit at a university teaching hos pital. Participants-A total of 135 women (mean (SD) age 63 (9) years) with pre-test probability of CAD greater than or equal to 80% were selected from a database of patients investigated by treadmill or dobutamine stress echo cardiography between 1995 and 1998. Main outcome measures-Patients were fol lowed up for occurrence of subsequent cardiac events (cardiac death, myocar dial infarction, admission with unstable angina, and revascularisation) usi ng a structured telephone interview and case note review. Results-Each patient had between two and seven (mean 3.5) CAD risk factors and pre-test probability of CAD greater than or equal to 80%. Ninety three patients (68.9%) had negative stress echocardiography. Mean (SD) follow up was 20.1 (8.5) months. There were six events in the positive stress echocar diography group (two cardiac deaths, one unstable angina, three revasculari sations), and one event in the negative stress echocardiography group. Cox regression analysis showed positive stress echocardiography (p=0.02) and ag e (p=0.03) to be the only univariate predictors and positive stress echocar diography to be the only independent predictor of future cardiac events (re lative risk 8.9, confidence interval 1.0 to 76.5, p=0.04). Cumulative event free survival to 38 months was 98% in the negative stress echocardiography and 50.7% in the positive stress echocardiography groups. Conclusion-In women with high pre-test likelihood of CAD: (1) negative stre ss echocardiography identifies a subgroup with low risk of cardiac events w ho do not require further invasive investigation and (2) positive stress ec hocardiography identifies a subgroup with increased risk of subsequent card iac events.