Clandestine ischemia in patients with vasospastic angina

Background Coronary vasospasms generally occur at rest, but can also be tri ggered by physical exercise. Anginal pain and ST-segment elevation may be s een during exercise-stress tests. ST-segment depression, due to nonocclusiv e vasospasms, has also been found to occur. When the result of a test is po sitive, scintigraphy usually reveals perfusion defects. True silent or clan destine ischemia (normal result of exercise test with perfusion defects) in these patients is very uncommon. Objective To stress the need for suspecting occurrence of coronary vasospas ms in order to perform a proper diagnosis. Methods Eight patients with angina were selected for this study. They had n egative results of exercise tests with perfusion defects detected by thalli um-201 tomography, normal coronary arteries and vasospasms. Maximal exercis e-stress tests with thallium-201 tomography were performed, Sizes of perfus ion defects were quantified by examining polar maps. Coronary angiography a nd then an intracoronary ergonovine test were performed for each patient. Results Significant defects were seen in territory of the right coronary ar tery, the left anterior descending artery, or both. Lung:heart ratio was no rmal in every case. The coronary arteries were normal and vasospasms were e licited with ergonovine in all the patients. Correspondence between the loc ation of perfusion defects and angiographic spasms was generally observed. After treatment with calcium antagonists and nitrates all of them improved and defects detected by thallium tomography were no longer found when tests were repeated. Conclusions Some patients with vasospastic angina may have normal results o f exercise-stress tests and reversible perfusion defects detectable by scin tigraphy. This finding must lead one to perform coronary angiography withou t administration of nitroglycerine beforehand and an ergonovine test if the coronary arteries are normal. Coron Artery Dis 11:383-390 (C) 2000 Lippinc ott Williams & Wilkins.