Objectives: In patients with chest pain suggestive of variant angina, we performed this prospective study to test the specificity and diagnostic validity of ergonovine echocardiography (detection of regional wall motion abnormality during bedside ergonovine challenge) as a screening procedure before coronary angiography.
Background: Spasm provocation test outside the catheterization room has generally not been accepted as a safe diagnostic method.
Methods: Ergonovine echocardiography was performed in 80 consecutive patients with chest pain syndrome after confirmation of negative treadmill or normal stress myocardial perfusion scan results using thallium-201. A bolus of ergonovine maleate was injected at 5-min intervals up to a total cumulative dosage of 0.35 mg with echocardiographic monitoring of left ventricular wall motion. A 12-lead electrocardiogram (ECG) was also recorded every 3 min after each ergonovine injection. Positive test results were development of regional wall motion abnormalities or transient ST segment elevation or depression >0.1 mV in any single lead of the 12-lead ECG. Coronary angiography was undertaken within 2 +/- 4 days (mean +/- SD) after ergonovine echocardiography, and the spasm provocation test with acetylcholine or ergonovine was performed in patients with normal angiographic findings or lumen diameter narrowing <70%.
Results: On the basis of angiographic criteria, 56 patients had coronary vasospasm; this finding was later ruled out in 19 patients with near-normal angiographic results by a negative response on the spasm provocation test. In the remaining five patients, coronary spasm provocation was not performed because they revealed a high degree of fixed stenosis (lumen diameter narrowing 97 +/- 4%). Ergonovine echocardiography could diagnose coronary vasospasm before angiography, with a sensitivity of 91% (51 of 56 patients, 95% confidence interval [CI] 84% TO 98%) and specificity of 88% (21 of 24 patients, 95% CI 75% to 100%). Of 53 patients showing regional wall motion abnormalities during ergonovine echocardiography, characteristic ST segment elevation in the simultaneously recorded ECG was observed in only 20 (38%). There were no complications, including myocardial infarction or fatal arrhythmia, during the test.
Conclusions: Ergonovine echocardiography before coronary angiography is safe and can be used as a reliable diagnostic screening test for coronary vasospasm in patients with negative treadmill or normal stress myocardial perfusion scan results. These findings suggest that invasive coronary angiography can be avoided in selected patients for the diagnosis of vasospastic angina.