Association between serum Mitofusin-2 levels, cardiac biomarkers, and inflammatory indices in patients with myocardial infarction with non-obstructive coronary arteries

Background Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a heterogeneous and clinically important phenotype in which improved risk stratification tools are needed, and mitochondrial dysfunction may contribute to its pathophysiology. We aimed to evaluate the association between serum Mitofusin-2 (MFN2) levels and cardiac biomarkers and hematologic inflammatory indices in MINOCA, and to determine their potential diagnostic and prognostic value. Methods A total of 30 MINOCA patients presenting with acute coronary syndrome (ACS) and non-obstructive coronary arteries on urgent coronary angiography, and 30 controls without an ACS presentation who underwent elective coronary angiography and had normal coronary arteries were included. Serum MFN2 was measured by ELISA at day 0 in both groups and repeated at day 3 in the MINOCA group, together with routine biochemistry, complete blood count-derived inflammatory indices and angiographic scores. Results Left ventricular ejection fraction (LVEF) was significantly lower, and both Gensini and SYNTAX scores were significantly higher compared with controls ( p < 0.05). At admission, no significant differences were observed in inflammatory indices between the control and MINOCA-0 groups, whereas by day 3 in MINOCA, neutrophil-to-lymphocyte ratio (NLR), C-reactive protein/albumin ratio (CAR), pan-immune-inflammation value (PIV), systemic inflammatory index (SII), monocyte-to-lymphocyte ratio (MLR), and systemic inflammation response index (SIRI) increased significantly and prognostic nutritional index (PNI), Glascow prognostic score (GPS), and lymphocyte-to-monocyte ratio (LMR) decreased significantly ( p < 0.05). Serum MFN2 levels increased significantly on day 3 compared with day 0 within the MINOCA group ( p < 0.0001). MFN2 showed a strong negative correlation with aspartate aminotransferase (AST) in both groups at day 0, and additionally demonstrated inverse associations with lymphocyte count in MINOCA (day 0–3). In Receiver Operating Characteristic (ROC) analyses, MFN2 did not show significant predictive/discriminative value for hospitalization for MINOCA either at presentation or when day 0 and day 3 MINOCA measurements were combined. Conclusion MFN2 demonstrates a delayed rise during early hospitalization in MINOCA but lacks diagnostic discrimination at presentation, supporting its evaluation as a longitudinal (rather than acute) biomarker candidate.