3-year follow-up of patients with coronary artery spasm as cause of acute coronary syndrome: the CASPAR (coronary artery spasm in patients with acute coronary syndrome) study follow-up.

OBJECTIVES: We sought to determine the prognosis of patients with acute coronary syndrome without culprit lesion and proof of coronary spasm during 3 years of follow-up.

BACKGROUND: Coronary artery spasm has been identified as an alternative cause for acute coronary syndrome (ACS) in patients without culprit lesion. In the CASPAR (Coronary Artery Spasm as a Frequent Cause for Acute Coronary Syndrome) study, we recently showed that ∼50% of ACS patients without culprit lesion, in whom intracoronary acetylcholine provocation was performed, had coronary spasm. However, data on prognosis in these patients are sparse.

METHODS: After 3 years of follow-up, data regarding the following end points were obtained: death (cardiac and noncardiac), nonfatal myocardial infarction, and recurrent angina leading to repeated coronary angiography. The analysis focused on patients with a culprit lesion (n = 270) and patients without a culprit lesion (n = 76) but with acetylcholine provocation (total n = 346).

RESULTS: In patients without culprit lesion, there was no cardiac death or nonfatal myocardial infarction during follow-up; 1 patient died due to a noncardiac cause. However, 38 of 76 patients reported persistent angina requiring repeated angiography in 3 cases (3.9%). Thirty of 270 patients with culprit lesion died due to a cardiac cause (11.1%) and 13 due to a noncardiac cause (4.8%). Eleven patients had nonfatal myocardial infarction (4.1%) and 27 repeated angiography due to persistent or recurrent angina (10%). Patients with a culprit lesion had a higher mortality and more coronary events compared with those without (p < 0.0005, log-rank test).

CONCLUSIONS: ACS patients without culprit lesion and proof of coronary spasm have an excellent prognosis for survival and coronary events after 3 years compared with patients with obstructive ACS. However, persistent angina represents a challenging problem in these patients, leading in some cases to repeated coronary angiography.