Background:
Exercise electrocardiography (ECG) is frequently used in the work-up of patients withsuspected coronary artery disease (CAD), however the accuracy is reduced in women.Cardiovascular magnetic resonance (CMR) stress testing can accurately diagnose CAD inwomen. To date, a direct comparison of CMR to ECG has not been performed.Methods and resultsWe prospectively enrolled 88 consecutive women with chest pain or other symptomssuggestive of CAD. Patients underwent a comprehensive clinical evaluation, exercise ECG, aCMR stress test including perfusion and infarct imaging, and x-ray coronary angiography(CA) within 24 hours. CAD was defined as stenosis [greater than or equal to]70% on quantitative analysis of CA.Exercise ECG, CMR and CA was completed in 68 females (age 66.4 +/- 8.8 years, number ofCAD risk factors 3.5 +/- 1.4). The prevalence of CAD on CA was 29%. The Duke treadmillscore (DTS) in the entire group was 3.0 +/- 5.4 and was similar in those with and withoutCAD (4.5 +/- 5.8 and 2.4 +/- 5.1; P = 0.12). Sensitivity, specificity and accuracy for CADdiagnosis was higher for CMR compared with exercise ECG (sensitivities 85% and 50%,P = 0.02, specificities 94% and 73%, P = 0.01, and accuracies 91% and 66%, P = 0.0007,respectively). Even after applying the DTS the accuracy of CMR was higher compared toexercise ECG (area under ROC curve 0.94 +/- 0.03 vs 0.56 +/- 0.07; P = 0.0001).
Conclusions:
In women with intermediate-to-high risk for CAD who are able to exercise and haveinterpretable resting ECG, CMR stress perfusion imaging has higher accuracy for thedetection of relevant obstruction of the epicardial coronaries when directly compared toexercise ECG.
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