Role of Vasospasm in Acute Coronary Syndrome

Background Previous studies have shown that ergonovine stress echocardiography (ESE) may be a valuable noninvasive tool for the diagnosis of vasospasm after the confirmation of no significant fixed stenosis. Methods and Results From May 1999 to January 2002, 52 patients who presented with acute coronary syndrome (ACS) and had normal or near-normal coronary angiograms were enrolled. A 50 μg bolus of ergonovine was given intravenously at 5-min intervals, until a positive result was observed or a total dose of 350 μg was given. After the ergonovine injection, positive results were found in 25 (48%) of 52 patients: 5 (26%) of 19 with unstable angina, 10 (53%) of 19 non-ST elevation myocardial infarction (MI) and 10 (71%) of 14 patients with ST elevation MI. Using univariate analysis, the elevation of troponin concentration, clinical diagnosis of MI, and ST segment elevation on initial electrocardiographic were significantly associated with positive stress test results. Conclusions Despite the limitation that coronary spasm was not confirmed angiographically with ergonovine provocation, ESE may be a useful technique for the noninvasive diagnosis of vasospasm. (Circ J 2005; 69: 39 - 43)