Objective Women with suspected angina without history of coronary artery disease (CAD) less frequently have flow-limiting stenosis (FL-CAD) and more often have microvascular disease, affecting predictive accuracy of stress echocardiography (SE) for detection of FL-CAD. We postulated that carotid plaque burden (CPB) assessment would improve detection of FL-CAD and risk stratification.

Methods Consecutive consenting patients assessed by SE on clinical grounds for new-onset chest pain also underwent simultaneous carotid ultrasound. Patients were followed for major adverse events (MAE): all-cause mortality, non-fatal myocardial infarction and unplanned revascularisation. Carotid plaque presence and burden (CPB) were assessed.

Results After a mean of 2617±469 days (range 17–3740), of 591 recruited patients, 573 (97%) outcome data (314 females) were obtainable. Despite lower pretest probability of CAD in females versus males (14.9±0.8 vs 20.5±1.3, respectively, p<0.0001), prevalence of myocardial ischaemia was similar (p=0.08). Females also had lower prevalence of both carotid plaque (p<0.0001) and FL-CAD (p<0.05). CPB improved the positive predictive value of SE for detection of FL-CAD (from 34.5% to 60%) in females but not in males. Absence of CPB in females with myocardial ischaemia ruled out FL-CAD in 93% versus 57% in males. CPB was the only independent predictor of MAE (p=0.012) in females, whereas in males both SE (p<0.0001) and CPB (p=0.003) remained significant.

Conclusion In females with new-onset stable angina without a history of cardiovascular disease, CPB improved the predictive accuracy of myocardial ischaemia for flow-limiting CAD. However, CPB provided incremental risk stratification in both sexes.