['The likelihood of a positive response with dipyridamole stress echocardiography (DSE) is directly related to the extent and severity of angiographically assessed coronary artery disease. Whether coronary lesion morphology--a known predictor of adverse cardiac events--may also modulate stress echo results remains unknown. The objective of our study was to assess the relation between stenosis lesion morphology and stress echocardiographic results.', 'High-dose (up to 0.84 mg/kg over 10 minutes) DSE and coronary angiographic data of 68 in-hospital patients (39 with stable angina, 29 with angina at rest) with nonoccluding, single-vessel disease at angiography and no previous myocardial infarction were analyzed. DSE was performed in all patients within 3 days of coronary angiography. An angiographic lesion was considered complex when irregular borders and/or intraluminal lucencies suggestive of ulcer and/or thrombus were present. According to angiographic lesion morphology, two groups were identified: group 1, with simple coronary lesions, and group 2, with complex coronary lesions. The two groups were matched for number of patients (n = 34 in each group), age (group 1, 59 +/- 9 versus group 2, 59 +/- 10 years, P = NS), and coronary artery stenosis severity by quantitative coronary angiography (group 1, 60 +/- 7% versus group 2, 58 +/- 6% diameter reduction, P = NS). The sensitivity of DSE was lower in patients of group 1 when compared with group 2 (53% versus 85%, P < .001). Among positive DSE, the low-dose (0.56 mg/kg over 4 minutes) positivity was less frequent in group 1 than in group 2 patients (17% versus 62%, P < .01). Exercise ECG was completed in 66 patients, and it was positive (> .1 mV ST-segment shift from baseline) in 20 out of 33 group 1 and in 22 out of 33 group 2 patients (61% versus 67%, P = NS). The peak rate-pressure product tended to be higher in group 1 than in group 2 patients (257 +/- 52 versus 240 +/- 64 mm Hg x beats per minute x 10(2), P = NS).'] Does complex coronary artery lesion morphology influence results of stress echocardiography?