POTENTIAL OF CAROTID ULTRASONOGRAPHY IN THE DIAGNOSIS OF CORONARY-ARTERY DISEASE - A COMPARISON WITH EXERCISE TEST AND VARIANCE ECG

Background and Purpose-Carotid artery atherosclerosis has been shown t o correlate with coronary artery disease (CAD). This study evaluates t he capacity of duplex ultrasonography of the carotid arteries as a too l in the diagnosis of CAD in comparison with exercise stress test and variance EGG. Methods-Carotid ultrasonography, exercise stress test, a nd variance ECG were performed in 184 symptomatic patients evaluated w ith coronary angiography. The diagnostic capacity of the studied nonin vasive methods was assessed by use of receiver operating characteristi c (ROC) curves constructed by successive consideration of several cut points, such as (1) the presence of unilateral/bilateral plaques and ( 2) cross-sectional common carotid artery (CCA) intima-media (IM) area hom 10 to 30 mm(2) for ultrasonography; (1) ST depression greater than or equal to 0.1 mV and greater than or equal to 0.2 mV with and (2) w ithout chest pain for exercise test; and electrical variability index from 50 to 100 for variance EGG. Results-Coronary angiography revealed the presence of CAD (greater than or equal to 50% luminal stenosis in 1 or more major epicardial arteries) in 147 patients (80%). Identific ation of carotid plaques on one or both sides and calculation of the l eft-sided (but not right-sided) CCA IM area provided a significant dis crimination (P<.001 and P<.01, respectively) of patients with CAD. The discriminating capacity of the ultrasound procedures was equal to tha t of variance ECG and exercise test with ST depression criterion only but somewhat lower than that of exercise test with the combined chest pain and ST depression criterion (P<.05). However, at the chosen cut p oints, carotid plaque identification offered higher sensitivity than e xercise test with either criterion (P<.01 and P<.001, respectively). C onclusions-Carotid ultrasonography is a useful diagnostic method that is comparable to exercise test and variance ECG for detection of CAD i n a high-prevalence population.