Abstract
OBJECTIVES: To assess the risk of major adverse cardiovascular and cerebrovascular events (MACCEs) in patients with ST-segment elevation myocardial infarction (STEMI) following percutaneous coronary intervention (PCI) by evaluating both the large coronary vessels and coronary microcirculation. METHODS: A total of 507 patients with STEMI undergoing successful percutaneous coronary intervention (PCI) were retrospectively enrolled from two centers. The optimal cut-off value (256.5 mmHg·s·m(-1)) of angio-based microvascular resistance (AMR) for predicting MACCEs was determined by ROC analysis. Combined with a quantitative flow ratio (QFR) threshold of 0.80, the patients were classified into 4 groups: Group 1 (QFR≥0.8, AMR<256.5; n=271), Group 2 (QFR≥0.8, AMR≥256.5; n=140), Group 3 (QFR<0.8, AMR<256.5; n=77), and Group 4 (QFR<0.8, AMR≥256.5; n=19). The primary endpoint was cardiac death or heart failure readmission within 2 years. RESULTS: Patients with elevated AMR (≥256.5 mmHg·s·m(-1)) had a significantly increased risk of MACCEs within two years after PCI (P<0.001). Kaplan-Meier analysis showed the lowest survival rate in patients with both QFR<0.8 and AMR≥256.5 mmHg·s·m(-1). Multiple linear regression analysis suggested that diabetes (P<0.001), hyperlipidemia (P<0.001), smoking (P<0.014), systemic inflammation response index (P<0.007), and platelet to lymphocyte ratio (P<0.001) were independently associated with elevated AMR levels. Restricted cubic spline regression revealed a non-linear relationship between AMR and MACCEs risk (non-linear P<0.001), and the hazard ratio for MACCEs increased markedly for an AMR beyond the threshold of 259.45 mmHg·s·m(-1). CONCLUSIONS: The integrated assessment of QFR and AMR allows effective prediction of MACCEs risk in STEMI patients after PCI, and elevated AMR is an independent predictor of significantly increased risk of MACCEs.