DETECT-MINOCA: Diagnose underlying aetiology with intravascular versus cardiac imaging

Dr Chinmay Khandkar, University of Sydney

Postgraduate Scholarship

Years funded: 2025 - 2028

Improving diagnosis in MINOCA patients

Patients with Myocardial Infarction with Non-Obstructive Coronary Arteries (MINOCA) are under-recognised in current practice, and are often discharged without a definitive diagnosis along with sub-optimal treatment. These patients have significant morbidity and mortality, and therefore it is imperative we recognise these patients. Whilst there are many diagnostic modalities available to investigate these patients, there is uncertainty around the ideal diagnostic pathway.

Comparing OCT and CMR to determine the best first-line test

Invasive modalities include intravascular imaging with Optical Coherance Tomography (OCT), with or without additional vasoreactivity testing using intra-coronary acetylcholine. The main non-invasive imaging technique is cardiac MRI (CMR). It is unclear whether patients should have intravascular imaging in the index angiogram first to identify ischaemic causes of MINOCA, or whether they should have a cardiac MRI post angiogram to potentially rule out non-ischaemic causes. Therefore this project aims to determine the diagnostic pathway that will best identify the underlying aetiology for these patients.

We will conduct a randomised control trial, where MINOCA patients (Patients with acute myocardial infarction with epicardial stenosis < 50%) are either randomised to upfront OCT +/- vasoreactivity testing in up to all 3 main epicardial vessels in the index angiogram, versus stopping the angiogram and performing a cardiac MRI. Further investigations may be required in either arm after the primary diagnostic test. Our primary outcome will be the diagnostic yield of the underlying MINOCA endotype after the first investigation (OCT +/- vasoreactivity vs CMR). We will also assess duration of hospital stay, major adverse cardiac events at 12 months, and safety outcomes. Our research will help inform future practice for MINOCA cases, to better serve this patient population.