Noninvasive ergonovine maleate provocative testing for coronary artery spasm: the need for routine thallium-201 imaging.

We administered ergonovine and used both electrocardiographic monitoring and thallium-201 [201Tl] imaging to detect reversible ischemia in 100 patients. Patients already established as having coronary artery spasm and those with nonbypassed, proximal, high-grade coronary artery stenosis were excluded. No complication occurred in any patient. The use of thallium imaging in addition to electrocardiographic monitoring resulted in a higher degree of sensitivity than did ECG monitoring alone. Fourteen patients demonstrated evidence of coronary artery spasm as documented by 201Tl imaging but of the 14, significant ECG changes occurred in only 50%, and classic ST segment elevation in 21%. Thus, in carefully selected patients the noninvasive provocation of coronary spasm can be accomplished safely, but ECG monitoring must be combined with thallium-201 imaging to achieve an acceptable degree of sensitivity.