Abstract

Aim: To evaluate the anatomical condition of the coronary arteries using coronary angiography and intravascular ultrasound in patients with myocardial infarction with non-obstructive coronary arteries (MINOCA).
Material and Methods: A prospective study included 94 patients with non-ST-elevation myocardial infarction (NSTEMI) and MINOCA. All patients underwent clinical examination and standard 12-lead electrocardiography (ECG). Coronary angiography (CAG) was performed in all patients, and intravascular ultrasound (IVUS) was performed in 18 patients.
Results: The mean age of the patients was 62.35 ± 10.33 years (range 33–86), with 78.7% males and 21.3% females. The mean admission cardiac troponin level was 0.83 ± 0.30 ng/mL. ST-segment depression was detected in 60.6%, T-wave inversion in 48.9%, and conduction abnormalities in 11.7% of patients. Normal coronary arteries were found in 19.1% of cases. Minimal luminal irregularities were observed in 28.7%, and mild to moderate stenoses in 52.1%. Single-vessel disease was diagnosed in 51.1%, two-vessel disease in 31.9%, and three-vessel disease in 17.0% of patients. Coronary spasm was identified in 8.5%, coronary thrombosis in 2.1%, atherosclerotic plaque disruption in 1.1%, and the coronary slow-flow phenomenon in 16.0% of patients. Among 18 patients with moderate stenosis, plaque rupture was detected in 38.9% of cases. Thrombotic masses were identified in 22.2%, and intimal thickening and signs of intraplaque hemorrhage in 11.1% of patients, respectively. Qualitative assessment of plaque morphology (n=7) revealed fibrous plaques in three cases, calcified plaques in one case, and lipid-rich plaques in one case.
Conclusion: Coronary angiography combined with IVUS enables the detection of subtle morphological changes in the vessel wall that are not visible with standard imaging. The use of intravascular ultrasound improves the accuracy of identifying microanatomical mechanisms underlying ischemic events and may serve as a basis for a personalized approach to patient management.

Key words: Non-ST-elevation myocardial infarction, myocardial infarction with non-obstructive coronary arteries, coronary angiography, intravascular ultrasound