Electrocardiogram in the Diagnosis of Acute Myocardial Infarction in Elderly Patients and Its Correlation with Lesion Severity

LU Cao; FU Huamin

doi:10.13919/j.issn.2095-6274.ZHJY202504028

Abstract：Objective To analyze the diagnostic efficacy of electrocardiogram in elderly patients with acute myocardial infarction(AMI),and to explore its correlation with the severity of the disease and the number of diseased blood vessels.Methods From January 2023 to December 2023,78 suspected elderly patients with AMI admitted to the 925th Hospital of the Joint Service Support Force of the Chinese People's Liberation Army were selected as the study subjects.According to the results of coronary angiography,patients were divided into AMI group(n=61)and non AMI group(n=17).The AMI group was further divided into ST segment elevation myocardial infarction(STEMI,n=46)group and non ST segment elevation myocardial infarction(NSTEMI,n=15)group.All patients were classified into single vessel(n=29),double vessel(n=24),and triple vessel(n=8)based on the number of diseased vessels(stenosis≥ 50％).Compare two sets of electrocardiogram repolarization parameters(QT interval,QTc interval,Tp Te interval),evaluate the diagnostic efficacy of electrocardiogram for AMI,and analyze the incidence of fQRS(fragmented QRS complex)and ST segment deviation amplitude.Results The QT interval,QTc interval,and Tp Te interval in the AMI group were significantly longer than those in the non AMI group(P＜0.05).The STEMI group was mainly characterized by ST segment elevation(93.48％,meet-ing the guidelines)and pathological Q waves(78.26％);The NSTEMI group mainly had ST segment depression(66.67％)and T wave inversion(53.33％).The sensitivity and specificity of electrocardiogram examination for the di-agnosis of AMI are 88.52％and 93.44％,respectively;The sensitivity and specificity of STEMI diagnosis were 93.48％and 97.83％,respectively;The sensitivity and specificity of NSTEMI diagnosis are 73.33％and 80.00％,respectively;AMI overall(Kappa=0.812)and STEMI(Kappa=0.868)showed high consistency,while NSTEMI(Kappa=0.677)showed moderate consistency.As the number of diseased vessels increases,the incidence of fQRS shows an increas-ing trend(P＜0.05),and the amplitude of ST segment deviation also shows an increasing trend(P＜0.05).Conclu-sion Electrocardiogram has high sensitivity and specificity in diagnosing elderly AMI,and is particularly prominent in STEMI.The repolarization parameters of electrocardiogram(such as QT interval,QTc interval,Tp Te interval)show certain differences in patients with different types of AMI.Electrocardiogram examination has important value in the early diagnosis and lesion evaluation of AMI.