Incidence and clinical characteristics of patients with ST-elevation acute myocardial infarction without obstructive coronary disease (MINOCA)

Introduction: MINOCA is an acute myocardial infarction without obstructive coronary disease, this definition was recently incorporated into the 4th universal definition of myocardial infarction. However, since it is an unconventional ischemic coronary syndrome in clinical practice, its etiology is very complex to elucidate and requires a differential diagnosis process to rule out other causes of cardiac injury. The objective of this study is to characterize patients with acute myocardial infarction without significant obstructive lesions included in the Argentine Registry of ST -segment Elevation Myocardial Infarction (ARGEN-IAM-ST). Methods: Prospective, multicenter national study including patients with STEMI within 36 hours of symptom onset. All patients studied with coronary angiography at admission were analyzed and those without significant obstructive lesions of the culprit artery were considered MINOCA. This MINOCA patients were compared with patients with significant atherosclerotic coronary lesions. Results: 30 patients with MINOCA out of 2894 patients entered in the registry (incidence: 1%). MINOCA patients were younger, had a similar proportion for gender, had fewer diabetics patients, and had a greater history of heart failure. They were admitted without heart failure and preserved ejection fraction. In-hospital mortality was 7%, with no significant difference compared to classic AMI. At discharge, they received P2Y12 inhibitors, statins, and beta-blockers in fewer proportion. Discussion: There was no predominance of the female gender as in other series. In-hospital mortality is high despite not having significant coronary disease. It is worth mentioning the low use of dual antiaggregating and statins.