一名心血管内科专家请将下面这段话翻译为英文用于学术论文的发表。这段话为：目的：探讨急性心肌梗死ami患者平面qrs-t夹角f-qrs-t角与冠状动脉病变程度之间的关系及对经皮冠状动脉介入治疗pci后发生主要心血管不良事件mace的预测价值。 方法：本研究共纳入300名在2018年1月至2020年1月期间接受pci的首次ami患者。计算每位患者的f-qrs-t角及gensini评分对其进行3

Purpose: To investigate the relationship between the planar QRS-T angle (F-QRS-T angle) and the degree of coronary artery disease (CAD) in patients with acute myocardial infarction (AMI), as well as its predictive value for major adverse cardiovascular events (MACE) after percutaneous coronary intervention (PCI). Methods: A total of 300 first-time AMI patients who underwent PCI between January 2018 and January 2020 were included in this study. The F-QRS-T angle and Gensini score were calculated for each patient, and they were followed up for 3 years. According to the Gensini score system, the subjects were divided into two groups: mild CAD group (Gensini score < 25 points) and severe CAD group (Gensini score ≥ 25 points). The size of the F-QRS-T angle was compared between the two groups, and its correlation with the degree of CAD was analyzed. ROC curve was used to explore the diagnostic efficiency of F-QRS-T angle for severe CAD. The subjects were divided into MACE group and non-MACE group according to whether MACE occurred during the follow-up period, and the correlation between F-QRS-T angle and MACE was analyzed. Multivariate logistic regression analysis was used to determine the risk factors for postoperative MACE in AMI patients. ROC curve was used to determine the diagnostic efficiency of F-QRS-T angle for postoperative MACE and to determine the diagnostic threshold. Results: 1. Compared with the mild CAD group, the F-QRS-T angle was significantly higher in the severe CAD group (P < 0.05), and it was positively correlated with the degree of CAD (rs = 0.583, P < 0.01). 2. ROC curve analysis showed that the optimal cutoff value of F-QRS-T angle for diagnosing severe CAD was 76.5°, with a sensitivity of 42.1% and a specificity of 90.1%, and the area under the ROC curve (AUC) was 0.665 (95%CI: 0.604-0.725, P < 0.05). 3. The levels of age, smoking rate, hypertension, diabetes, neutrophils (NEUT), C-reactive protein (CRP), homocysteine (HCY), total cholesterol (TC), triglycerides (TG), and low-density lipoprotein cholesterol (LDL-C) were higher in the severe CAD group (P < 0.05). 4. The F-QRS-T angle, Gensini score, age, smoking rate, hypertension, diabetes, combined dyslipidemia, white blood cells (WBC), NEUT, HCY, CRP, and creatinine (Cr) levels were significantly higher in the MACE group (P < 0.05), and there was a positive correlation between F-QRS-T angle and the occurrence of MACE (rs = 0.498, P < 0.001). 5. Multivariate logistic regression analysis showed that F-QRS-T angle (OR: 1.075, 95%CI: 1.037-1.113), age (OR: 1.224, 95%CI: 1.093-1.371), smoking (OR: 10.36, 95%CI: 1.369-78.406), combined diabetes (OR: 7.351, 95%CI: 1.228-44.012), combined dyslipidemia (OR: 9.42, 95%CI: 1.345-65.972), NEUT (OR: 1.451, 95%CI: 1.035-2.036), Cr (OR: 1.119, 95%CI: 1.046-1.197), and Gensini score (OR: 1.023, 95%CI: 1.001-1.045) were independent predictors of MACE (P < 0.05). 6. The optimal cutoff value of F-QRS-T angle for diagnosing postoperative MACE in AMI patients was 85.5°, with a sensitivity of 78.6%, a specificity of 94.6%, and an AUC of 0.914 (95%CI: 0.858-0.970, P < 0.05). Conclusion: 1. The F-QRS-T angle in AMI patients is positively correlated with the severity of CAD. 2. F-QRS-T angle is a simple, fast, non-invasive evaluation index that has certain diagnostic value for severe CAD in AMI patients and can be used to evaluate the degree of coronary artery stenosis in AMI patients. 3. F-QRS-T angle is an independent predictor of MACE in AMI patients after PCI. 4. Determining the diagnostic threshold of F-QRS-T angle may help clinical doctors to take corresponding intervention strategies to improve the prognosis of AMI patients. Keywords: planar QRS-T angle, acute myocardial infarction, major adverse cardiovascular events, Gensini score.