Randomized Evaluation of Beta Blocker and ACEI/ARB Treatment in MINOCA Patients - MINOCA-BAT

Large-scale use of acute coronary angiography has revealed a large portion of AMI without angiographically obstructive (defined as ≥50% diameter stenosis) coronary artery disease (CAD). The term "myocardial infarction with non-obstructive coronary arteries" (MINOCA) has been coined for this entity. MINOCA occurs in 5-10% of all patients with AMI and these patients are younger and more often females compared to patients with AMI and obstructive CAD. The 1-year mortality after MINOCA was found to be 3.5% in the systematic review by Pasupathy et al.. There are no randomized clinical trials in MINOCA patients evaluating effects of secondary preventive treatments proven beneficial in patients with classic AMI. However, in an observational study with propensity score matched comparisons the risk of experiencing a Major Adverse Cardiac Event (MACE) was 18% lower in patients treated with ACEI/ARB compared to no ACEI/ARB; in patients on beta blockers compared to patients not using beta blockers there was a non-significant 14% reduction in MACE. The primary objective of this multi-national, multi-center pragmatic randomized clinical trial is to determine whether oral beta-blockade compared to no oral beta-blockade, and whether ACEI/ARB compared to no ACEI/ARB, reduce the composite endpoint of death of any cause and readmission because of AMI, ischemic stroke or heart failure in patients discharged with myocardial infarction with non-obstructive coronary artery disease (MINOCA) and with no clinical signs of heart failure and with LV systolic ejection fraction ≥40%. PRIMARY ENDPOINT: Time to death of any cause or readmission because of myocardial infarction, ischemic stroke or heart failure. SECONDARY ENDPOINTS: Time to: * All-cause mortality * Cardiovascular mortality * Readmission because of AMI * Readmission because of ischemic stroke * Readmission because of heart failure * Readmission because of unstable angina pectoris * Readmission because of atrial fibrillation. Safety: Time to readmission because of: * AV-block II-III, hypotension, syncope or need for pacemaker * Acute kidney injury * Ventricular tachycardia/fibrillation