Myocardial infarction with non-obstructive coronary arteries in young women presenting with ST-segment elevation myocardial infarction: a case series

Introduction. Myocardial infarction with non-obstructive coronary arteries (MINOCA) is an increasingly recognised entity, with comparable mortality to myocardial infarction with obstructive coronary artery disease (CAD).Case presentation. We present the cases of two young females presenting to hospital with ST-segment elevation myocardial infarction without obstructive CAD. Common to both cases was the acute onset of chest pain with no prior cardiac history, minimal cardiac risk factors, and the use of hormone-based contraception. The first patient had an ostially occluded left anterior descending artery (LAD). Flow was restored with balloon inflation and the administration of tirofiban. However, no underlying obstructive CAD was identified, which was confirmed with repeat angiography and optical coherence tomography. The cause was later attributable to plaque erosion, after learning the results of a normal thrombophilia screening. The second patient had ST-segment resolution on arrival to the catheter lab, and on angiography, she had TIMI II flow down the LAD due to significant thrombus burden. Similarly, balloon inflation and tirofiban were administered to improve flow, and non-obstructive CAD was confirmed with repeat angiography and OCT 48 hours later. As with patient 1, this patient too had normal thrombophilia screening results. Both patients were discharged with dual-antiplatelet therapy and secondary prevention, and were advisedagainst hormone-based contraception.Discussion. Patients with MINOCA tend to be younger, with a higher female-to-male preponderance. Multiple causes have been identified, highlighting the importance of following a diagnostic algorithm. This will enable correct treatment, which may differ from that for patients with obstructive coronary disease, thus improving prognosis