LAUSR

Background: Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a complex and diagnostically challenging entity. Case: A 62-year-old female with recent COVID19 infection presented with chest pain. She was discharged just one week prior for NSTEMI, with mild non-obstructive CAD by left heart catheterization (LHC) and a normal transthoracic echocardiogram. This admission, Initial Troponin I peaked at 0.87 ng/mL and ECG without ischemic changes. Cardiac MRI (CMR) showed no myocarditis/pericarditis but moderate-severely hypokinetic apical cap, distal inferior and septal walls, with a small focus of subendocardial scar/infarction involving the distal septum (Fig.1A,B,C). LHC showed severe vasospasm in the right coronary artery and left anterior descending artery (Fig. 1D,E), which resolved after intracoronary nitroglycerin (Fig. 1F). With initiation of isosorbide mononitrate to manage coronary vasospasm, the patient’s symptoms improved. At 6-month follow-up, patient was doing well with no repeat hospitalizations. Decision-making: Even though initial workup did not identify a clear etiology, CMR was pivotal in prompting further evaluation that revealed severe coronary vasospasm. Given the transient nature of vasospasm, it is likely this had resolved prior to her initial LHC, but was caught on repeat imaging. Conclusion: CMR is a key diagnostic tool in preliminary investigation of MINOCA when a clear cause is not found, and can alter next steps in management. [Formula presented]