The Role of the MAPH Score in Predicting Thrombus Burden in Unstable Angina Pectoris

Aim: Hemorheologic and viscosity-related parameters, including the Mean Platelet Volume–Age–Protein–Hematocrit (MAPH) score, have shown promising performance in predicting angiographic thrombus burden in ST segment elevation myocardial infarction (STEMI) and non-ST segment elevation myocardial infarction (NSTEMI). However, their diagnostic value in unstable angina pectoris (UAP) remains unclear. This study aimed to evaluate the predictive performance of the MAPH score compared with low-shear rate (LSR) and high-shear rate (HSR) blood viscosity parameters for estimating coronary thrombus burden in UAP.Material and Methods: In this single-center retrospective observational study, 320 adult patients diagnosed with UAP who underwent coronary angiography were included. Thrombus burden was graded using the TIMI thrombus classification. Two cut-offs (TIMI ≥4 and ≥3) were analyzed separately. MAPH, LSR, and, HSR were calculated from admission laboratory values. Diagnostic performance was assessed using receiver operating characteristic (ROC) analysis.Results: High thrombus burden was observed in 10.9% (TIMI ≥4) and 17.2% (TIMI ≥3) of patients. Age, diabetes mellitus, history of coronary artery disease, and troponin levels were higher in the high-thrombus-burden groups, but MAPH, LSR, and HSR values did not differ significantly between the groups. ROC analysis demonstrated limited discrimination for all parameters. For TIMI ≥4, AUC values were 0.552 for MAPH, 0.491 for HSR, and 0.500 for LSR. For TIMI ≥3, AUCs were 0.547, 0.516, and 0.519, respectively.Conclusion: In patients with UAP, MAPH, HSR, and LSR the ability to predict angiographic thrombus burden was limited.