Cardiovascular magnetic resonance in myocardial infarction with non-obstructive coronary arteries

Aim. To analyze diagnostic performance of cardiovascular magnetic resonance (CMR) in patients, presented with myocardial infarction with nonobstructed coronary arteries (MINOCA). Materials ant methods. 46 consecutives patients presented with myocardial infarction without evidence of obstructive coronary disease on angiography between January, 1 2018 and October 1, 2019 were included in the study. All patients underwent CMR within 10 days after admission. MRI was performed on 1.5 T Magnetic Resonance Imaging (MRI) using comprehensive protocol (T2-images, Cine-CMR, late gadolinium enhancement (LGE)). Results. CMR revealed myocardial infarction (MI) pattern in 14 patients (30.4%), myocarditis in 12 (26.1%), hypertrophic cardiomyopathy in 6 (13.1%). In 14 patients (30.4%) no LGE was observed. Notably in 2 patients without LGE features of takotsubo syndrome were noted. Mean age was significantly lower in patients with MI versus patient with non-ischemic causes of MINOCA (56.1±12.3 vs 64.6±12.8; p =0.04). ST elevation at admission frequency didn’t differ between MI and non-ischemic patients (35.7% vs 25.0%; p =0.76). However MI patients had significantly increased troponin level, 0.87 [0.22; 1.85] vs 0.22 [0.07; 0.38]; p =0.008. CMR allowed to establish the precised clinical diagnosis in 73.9% of the cases. Conclusion. Clinical data doesn’t allow to differentiate ischemic or non-ischemic causes of MINOCA. However, CMR establish the correct diagnosis in most cases.