Abstract Introduction Cardiac MRI (CMR) helps to determine the underlying aetiology of those presenting with a working diagnosis of Myocardial Infarction with Non-Obstructive Coronary Arteries (MINOCA) and guides further management and risk factors modification1. CMR performed within 14 days has the highest yield and current guidelines also advocate early CMR2. Local CMR service was established in our DGH in November 2022. We reviewed the effectiveness of in-house CMR service, and the reclassification of patients into ischaemic and non-ischaemic categories based on CMR findings. Methods Suspected MINOCA patients were identified from the Myocardial Infarction National Audit Project (MINAP) registry and local CMR database, by doing case review of every patient who presented with troponin positive chest pain at our centre and subsequently underwent invasive coronary angiography showing non-obstructive coronaries. The number of CMR studies, and proportion of studies performed within 2 weeks of presentation for patients with probable MINOCA before and after establishment of local CMR service April 2019 to April 2021 (Group 1) vs. Nov 2022 to Oct 2024 (Group 2) was compared. For group 2, we also looked at how CMR reclassified patients into ischemic and non-ischemic causes of troponin positive chest pain presentation and reviewed the rates of re-presentation with chest pain to emergency department. Results CMR was performed in only 13 patients from Group 1 vs 124 in Group 2. No scans (0/13, 0%) were completed within 2 weeks of referral with out of area CMR service (group 1) versus 107/124 (86%) of studies were undertaken within 2 weeks of request in group 2 patients (p0.001). In Group 2, CMR revealed that only 20(16%) patients had true MINOCA while 63(51%) patients had non-ischemic aetiology Myocarditis 39(32%), Takotsubo cardiomyopathy 21(17%), other cardiomyopathy 3(2%), and 41(33%) patients had normal scans or non-specific findings. The patients were followed up from one month after index presentation to a mean follow up of 15.3 (± 6.7) months. A total of 31(25%) patients re-presented with chest pain during follow-up period, further grouping of those was as follows: MINOCA 7/20 (35%) patients, non-ischaemic causes 17/63 (27%) and normal 6/41 (15%) scans. Conclusion Local CMR service helps to achieve timely scans and aids in reclassifying patients with suspected MINOCA into ischemic and non-ischemic causes to guide appropriate management. The rate of re-presentation with chest pain was noted to be higher for patients with underlying ischaemic aetiology compared with non-ischemic aetiology established on CMR.CMR completion times CMR results
Ahmed et al. (Thu,) studied this question.