请你继续充当心血管病学的专家帮助学生进行论文的去重修改。如果文章中连续13个字一样就算重复。你需要通过调整主谓宾语序、替换同义词、增减字数等方法来达到论文去重的目的。请你修改下面这段话：Purpose To investigate the relationship between the planar QRS-T angle F-QRS-T angle and the degree of coro

Purpose: This study aimed to explore the correlation between planar QRS-T angle (F-QRS-T angle) and coronary artery disease (CAD) severity in acute myocardial infarction (AMI) patients, as well as its predictive value for major adverse cardiovascular events (MACE) after percutaneous coronary intervention (PCI).

Methods: This study included 300 first-time AMI patients who underwent PCI between January 2018 and January 2020. The F-QRS-T angle and Gensini score were calculated and the patients were followed up for 3 years. According to the Gensini score system, patients were divided into mild CAD group (Gensini score < 25) and severe CAD group (Gensini score ≥ 25). The F-QRS-T angle was compared between the two groups and its correlation with CAD severity was analyzed. ROC curve was used to explore the diagnostic efficiency of F-QRS-T angle for severe CAD. Patients were divided into MACE and non-MACE groups based on MACE occurrence during follow-up, and the correlation between F-QRS-T angle and MACE was analyzed. Multivariate logistic regression analysis was used to determine risk factors for postoperative MACE in AMI patients. ROC curve was used to determine the diagnostic threshold of F-QRS-T angle for postoperative MACE.

Results: 1. F-QRS-T angle was significantly higher in the severe CAD group compared to the mild CAD group (P < 0.05), and it was positively correlated with CAD severity (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. 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 MACE occurrence (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. F-QRS-T angle is positively correlated with CAD severity in AMI patients. 2. F-QRS-T angle is a simple, fast, and non-invasive evaluation index that has diagnostic value for severe CAD in AMI patients and can evaluate coronary artery stenosis degree. 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 intervene appropriately and improve prognosis of AMI patients.

Keywords: planar QRS-T angle, acute myocardial infarction, major adverse cardiovascular events, Gensini score.