Abstract:Aim To apply coronary angiography derived index of microcirculatory resistance (caIMR) to evaluate the effect of coronary microcirculation perfusion on myocardial remodeling after interventional therapy in patients with acute anterior ST segment elevation myocardial infarction (STEMI). Methods This was a cross-sectional study.The analysis was performed among the patients who were hospitalized for acute anterior STEMI in the First Department of the Second Affiliated Hospital of Dalian Medical University from January 2021 to July 2022 and received percutaneous coronary intervention (PCI) with regtelar follow-up visits. The patients were divided into low caIMR (L-caIMR) group, medium caIMR (M-caIMR) group and high caIMR (H-caIMR) group according to the results of caIMR. The results of echocardiography at perioperative period, 1 month, 3 months, 6 months and 1 year were analyzed and compared, including left atrial diameter (LAD), left ventricular end-diastolic diameter (LVEDD), interventricular septum thickness (IVST), mitral orifice flow velocity E/A, mitral annular septum e′ and mitral annular wall e′, etc. The difference of interleukin-1β (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and other inflammatory factors in peripheral blood of the three groups were also compared. Results A total of 75 patients diagnosed with acute anterior STEMI were recruited, including 55 males. The L-caIMR group, M-caIMR group, and H-caIMR group had 6,6 and 23 cases, respectively. Compared with the L-caIMR group, the LAD and IVST in the M-caIMR group and the H-caIMR group exhibited an increasing tendency one month after PCI, and the increase in the H-caIMR group was more significant than that in the M-caIMR group (P<0.05). The ejection fraction in the H-caIMR group was notably lower than that in the L-caIMR group and the M-caIMR group at 1 and 3 months after PCI (P<0.05). Compared with the L-caIMR group, the mitral flow velocity E/A at 6 months after PCI, and the e′ at the septal side and the lateral wall of the mitral annulus at 1,3, and 6 months after PCI were significantly reduced in the M-caIMR and H-caIMR groups(P<0.05). Compared with the L-caIMR group, the levels of IL-1β, IL-6, and TNF-α showed an increasing trend in the M-caIMR group and the H-caIMR group, and the increase was greater in the H-caIMR group than that in the M-caIMR group (P<0.05). Multivariate analysis revealed that caIMR was a factor influencing the levels of IL-1 β and IL-6 (P<0.05). Conclusion CMD may be involved in the process of myocardial remodeling in patients with acute anterior STEMI after PCI, in which inflammation plays a role.