Predictive value of angiographic microvascular resistance for left ventricular thrombus in anterior ST-segment elevation myocardial infarction

Angiographic microvascular resistance (AMR) serves as an effective metric for assessing coronary microvascular status. The aim of this study was to investigate the predictive value of AMR for left ventricular thrombus (LVT) in ST-segment elevation myocardial infarction. This study enrolled 401 consecutive patients with anterior STEMI who underwent primary percutaneous coronary intervention (PPCI) between May 2019 and July 2023. AMR was measured immediately after PPCI via coronary angiography. LVT was identified during hospitalization through cardiac magnetic resonance imaging (CMR) or transthoracic echocardiography (TTE). Major adverse cardiac and cerebrovascular events (MACCEs) were recorded over 36 months follow-up. The predictive value of AMR was evaluated by logistic regression and receiver operating characteristic (ROC) analysis. Kaplan-Meier analysis was performed to estimate event-free rates for MACCEs. LVT was identified in 38 out of 401 anterior STEMI patients (9.5%). After adjusting for confounders through multivariable analysis, AMR was found to be an independent predictor of LVT (odds ratio [OR] 1.240 per 0.1 mmHg·s/cm, 95% confidence interval [CI]: 1.131-1.359, P < 0.001). ROC analysis demonstrated an area under the curve (AUC) of 0.742. For LVT, AMR provided modest incremental predictive value over established risk factors (continuous net reclassification improvement, 0.826 [95% CI: 0.523-1.129]; P < 0.001). Furthermore, Kaplan-Meier analysis revealed MACCEs for anterior STEMI patients with AMR ≥ 2.82 (log-rank P < 0.001). AMR is an independent predictor of LVT in anterior STEMI, providing incremental predictive value beyond traditional risk factors, and may be utilized to identify patients at risk for LVT.