Reinfarction in Patients with Myocardial Infarction with Nonobstructive Coronary Arteries (MINOCA) : Coronary Findings and Prognosis.

BACKGROUND: Myocardial infarction (MI) with nonobstructive coronary arteries (MINOCA) is common. There are limited data on the mechanisms and prognosis for reinfarction in MINOCA patients. METHODS: In this observational study of MINOCA patients hospitalized in Sweden and registered in the SWEDEHEART registry between July 2003 and June 2013 and followed until December 2013, we identified 9092 unique patients with MINOCA of 199,163 MI admissions in total. The 570 (6.3%) MINOCA patients who were hospitalized due to a recurrent MI constituted the study group. RESULTS: The mean age was 69.1 years and 59.1% were women. The median time to readmission was 17 months. A total of 340 patients underwent a new coronary angiography and 180 (53%) had no obstructive coronary artery disease (CAD) and 160 (47%) had obstructive CAD; 123 had 1-vessel, 26 had 2-vessel, 9 had 3-vessel disease, and 2 had left main together with 1-vessel disease. Male sex, diabetes, peripheral vascular disease, higher levels of creatinine, and ST elevation at presentation were more common in patients with MI with obstructive CAD than in patients with a recurrent MINOCA. Mortality during a median follow-up of 38 months was similar whether the reinfarction event was MINOCA or MI with obstructive CAD 13.9% vs 11.9% (P = .54). CONCLUSIONS: About half of patients with reinfarction after MINOCA who underwent coronary angiography had progression of coronary stenosis. Angiography should be strongly considered in patients with MI after MINOCA. Mortality associated with recurrent events was substantial, though there was no difference in mortality between those with or without significant CAD