Association Between Plasma Fibrinogen Level and the Risk of Myocardial Infarction With Non-Obstructive Coronary...

Myocardial infarction with non-obstructive coronary arteries (MINOCA) represents a heterogeneous clinical entity with an unclear pathophysiological basis. Fibrinogen is a key coagulation factor and inflammatory marker that has been associated with atherosclerotic burden in myocardial infarction (MI). However, the role of fibrinogen in MINOCA remains to be established. Therefore, this study aimed to investigate the association between plasma fibrinogen levels and the occurrence of MINOCA, and to evaluate the potential value of fibrinogen assessment in clinical characterization and early identification.

This retrospective study initially screened 1759 patients diagnosed with acute myocardial infarction (AMI) who underwent coronary angiography. A total of 287 patients were analyzed after applying the inclusion and exclusion criteria: 87 with MINOCA and 200 with the MI alongside obstructive coronary artery disease (MI-CAD). A logistic regression analysis was used to assess the association between fibrinogen levels and MINOCA, with subgroup and interaction analyses performed. Receiver operating characteristic (ROC) and restricted cubic spline (RCS) analyses were conducted as supplementary evaluations.

Fibrinogen levels were significantly lower in the MINOCA group compared to the MI-CAD group (p = 0.005). Lower fibrinogen levels were independently associated with increased odds of MINOCA in the multivariate analysis (odds ratio (OR): 0.654, 95% confidence interval (CI): 0.483-0.885; p = 0.006). Quartile analysis revealed a significant inverse trend between fibrinogen levels and risk of MINOCA (p for trend = 0.006), which was further confirmed by a consistent dose-response relationship in the spline analysis (p for overall = 0.035; p for nonlinear = 0.590). The association remained robust across several subgroups. Fibrinogen alone showed a limited discriminative ability (area under the curve (AUC) = 0.605, 95% CI: 0.534-0.675; p = 0.005).

Lower plasma fibrinogen levels were independently associated with the occurrence of MINOCA, suggesting a potential role in its pathophysiology and the early identification of this condition. Fibrinogen alone has limited discriminative utility; however, fibrinogen may contribute to multi-marker approaches for determining and managing MINOCA patients.