Clinical Profiles and Diagnostic Pathways in MINOCA: A Single-Centre Experience From Southwest Sydney

Background & Aim Myocardial infarction with non-obstructive coronary arteries (MINOCA) is defined as acute myocardial infarction (AMI) without obstructive coronary artery disease (no stenosis ≥50%). It affects 6%–8% of AMI patients without angiographic obstruction and represents a heterogeneous entity with diverse underlying mechanisms. Contemporary guidelines emphasise systematic evaluation, including cardiac magnetic resonance imaging (CMR) and intravascular coronary imaging, to identify mechanisms such as plaque rupture or erosion. However, real-world diagnostic pathways remain variable. This study aimed to characterise clinical profiles and diagnostic pathways, particularly CMR utilisation, in patients presenting with MINOCA at a single centre in Southwest Sydney, Australia. Method A retrospective observational study was conducted that included patients presenting with non-ST elevation myocardial infarction (NSTEMI) between January 2024 and April 2025 who demonstrated non-obstructive coronary arteries on angiography. Demographic characteristics, clinical presentation, biochemical profile, and advanced imaging utilisation were analysed. Results 145 patients met the inclusion criteria. MINOCA was more common in females (54.2%), with most aged 60–80 years (57%). Chest pain was the predominant symptom (69.4%). 11% had prior percutaneous coronary intervention. CMR referral occurred in 16% of cases, of whom only 12.5% underwent imaging. Intravascular imaging was performed in 1%. Conclusions In this cohort, MINOCA demonstrated female predominance with chest pain as a presentation. Advanced imaging was markedly underutilised. These findings demonstrate a significant gap between contemporary guideline recommendations and real-world practice, supporting the implementation of a structured diagnostic pathway.