Diagnostic value for coronary artery disease of chest pain during dipyridamole-thallium stress testing.

Intravenous dipyridamole with thallium imaging permits stress testing for coronary artery disease (CAD) without exercise. Chest pain may occur with dipyridamole-thallium testing, but its diagnostic significance is uncertain. Forty-five patients who had coronary angiography, no revascularization and chest pain during dipyridamole-thallium testing were identified. These patients were matched blindly by sex and age to 45 patients who had coronary angiography, no revascularization and no chest pain reported during the dipyridamole-thallium test. In the groups with versus without chest pain, 9 versus 24% had no CAD, 16 versus 16% had 1-vessel disease, 38 versus 29% had 2-vessel CAD and 38 versus 29% had 3-vessel CAD. These differences did not achieve statistical significance. Also, there were no evident differences in the severity of angiographic CAD by vessel or by percent of stenosis (p greater than 0.50). There was only a moderate association with ischemic ST changes (40 versus 16%, p less than 0.02). Chest pain with concurrent ischemic ST changes also failed to predict any difference in distribution or severity of angiographic stenoses. We conclude that chest pain during dipyridamole-thallium testing is not closely related to the severity of CAD and has little diagnostic value.