Cardiology Letters 2022, 31(2):120-130

Diagnostics of the substrate of myocardial damage after overcoming MINOCA and its clinical significance

Horániová L

Kardiocentrum Nitra, Slovenská republika

Introduction: Myocardial infarction with nonobstructive coronary arteries (MINOCA) represents an etiologically heterogeneous group of patients, with a differing prognosis compared to patients with myocardial infarction (MI) of atherosclerotic etiology. In comparison to a healthy population, MINOCA carries a 4-fold higher risk of annual mortality from any cause and a high risk of major preventable causes of cardiovascular events (MACE). Currently the diagnosis of MINOCA is not sufficiently established in Slovakia in the fields of interventional cardiology and cardio-radiological imaging.

Methods: In our cohort, we analyzed 1131 patients hospitalized at Kardiocentrum Nitra with the diagnosis of myocardial infarction in 2020. Forty seven patients met the criteria for MI without a coronary angiogram correlate. Of the following patients, 39 underwent magnetic resonance (MR) at the JESSENIUS diagnostic center. After identification of ischemic pathology, patients followed subsequent examination to analyze the most probable etiology of the MI.

Results: In our cohort, 31% of patients were clearly defined as MINOCA of ischemic etiology by MR. Other findings included myocarditis, Takotsubo syndrome, cardiomyopathies, and some patients had a negative MR finding in whom type 2 ischemia triggers were retrospectively identified. According to the distribution and extent of ischemia, we defined three groups of MR images: solitary ischemic area (group 1), multifocal zones of ischemia in multivessel blood supply areas (group 2), and ischemic area correlating with a single vessel blood supply (group 3). By combining the analysis of MR findings of the individual groups and their coronary angiogram correlate, we defined the most probable etiology of ischemia. Patients in groups one and two had a negative coronary angiogram. We concluded that peripheral embolization was the most probable etiology of ischemia within these groups. Group three comprised a heterogeneous group of patients, and it was not possible to define a clear etiology from the available examinations. However, atherosclerotic, thromboembolic and vasospastic causes are possible.

Conclusion: The presented diagnostic algorithm consisting of a combination of invasive and imaging diagnostic measures helps to more accurately determine the etiology of patients with MINOCA, with a direct impact on proper therapeutic management and the adequate secondary prevention of possible MACE.

Keywords: MINOCA; magnetic resonance of the heart; myocardial ischemia; quantification of myocardial ischemia

Published: February 1, 2022  Show citation