Presentation, Clinical Profile, and Prognosis of Young Patients With Myocardial Infarction With Nonobstructive Coronary Arteries (MINOCA): Results From the VIRGO Study.

BACKGROUND

We compared the clinical characteristics and outcomes of young patients with myocardial infarction with nonobstructive coronary arteries (MINOCA) versus obstructive disease (myocardial infarction due to coronary artery disease [MI-CAD]) and among patients with MINOCA by sex and subtype.

METHODS AND RESULTS

Between 2008 and 2012, VIRGO (Variation in Recovery: Role of Gender on Outcomes of Young AMI Patients) prospectively enrolled acute myocardial infarction patients aged 18 to 55 years in 103 hospitals at a 2:1 ratio of women to men. Using an angiographically driven taxonomy, we defined patients as having MI-CAD if there was revascularization or plaque ≥50% and as having MINOCA if there was <50% obstruction or a nonplaque mechanism. Patients who did not have an angiogram or who received thrombolytics before an angiogram were excluded. Outcomes included 1- and 12-month mortality and functional (Seattle Angina Questionnaire [SAQ]) and psychosocial status. Of 2690 patients undergoing angiography, 2374 (88.4%) had MI-CAD, 299 (11.1%) had MINOCA, and 17 (0.6%) remained unclassified. Women had 5 times higher odds of having MINOCA than men (14.9% versus 3.5%; odds ratio: 4.84; 95% confidence interval, 3.29-7.13). MINOCA patients were more likely to be without traditional cardiac risk factors (8.7% versus 1.3%; <0.001) but more predisposed to hypercoaguable states than MI-CAD patients (3.0% versus 1.3%; =0.036). Women with MI-CAD were more likely than those with MINOCA to be menopausal (55.2% versus 41.2%; <0.001) or to have a history of gestational diabetes mellitus (16.8% versus 11.0%; =0.028). The MINOCA mechanisms varied: a nonplaque mechanism was identified for 75 patients (25.1%), and their clinical profiles and management also varied. One- and 12-month mortality with MINOCA and MI-CAD was similar (1-month: 1.1% and 1.7% [=0.43]; 12-month: 0.6% and 2.3% [=0.68], respectively), as was adjusted 12-month SAQ quality of life (76.5 versus 73.5, respectively; =0.06).

CONCLUSIONS

Young patients with MINOCA were more likely women, had a heterogeneous mechanistic profile, and had clinical outcomes that were comparable to those of MI-CAD patients.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00597922.