Noninvasive prediction of coronary artery disease progression by comparison of serial exercise electrocardiography and dipyridamole stress echocardiography.

BACKGROUND: The possibility of noninvasive prediction of angiographically assessed coronary artery disease (CAD) progression by comparison of serial studies of exercise electrocardiography (EET) and dipyridamole stress echocardiography (DET) is not known. AIM: To assess the relative value of EET and DET in predicting angiographically assessed progression of CAD.
METHODS: From the Institute of Clinical Physiology, National Research Council, Pisa Italy stress echo data bank (1983-1998), we selected 46 patients with two repeated EET, DET and coronary angiography (CA) in two different hospital admissions (46+/-30 months). A priori, angiographic progressors were defined as any stenosis progression to occlusion and/or any stenosis >30% with >20% stenosis progression measured by visual and quantitative CA. EET progressors were defined as a previous negative test becoming positive or as a positive test with decrease in ischemic threshold response in the second test. DET progressors were defined as previous negative test becoming positive or as a positive test with a more severe ischemic response in the second test.
RESULTS: Angiographic progressors were 31/46 patients (67%) and angiographic nonprogressors were 15/46 (33%). When angiography was taken as the gold standard, there were no differences in sensitivity for EET and DET (87 vs. 87%). Specificity was significantly higher for DET (93 vs. 40% p =< 0.001). By kappa statistics DET had a good concordance (kappa = 0.768) and EET a poor concordance (kappa = 0.299) with angiographic progression.
CONCLUSION: DET is more accurate than EET at predicting angiographically assessed CAD progression.