Objective To investigate the value of electrocardiographic parameters in assessing severe coronary artery lesions in patients with coronary artery disease.Methods A total of 364 patients with coronary heart disease admitted to the Second Affiliated Hospital,Zhengzhou University from January 2022 to September 2023 were selected as the subjects.The patients were divided into severe lesion group(n=123)and non-severe lesion group(n=241)based on the Gensini score.The two groups were compared in terms of baseline data and electrocardiographic parameters.Logistic regression was used to analyze the factors affecting severe lesions and the efficacy of ECG parameters assessment.A column-line plot of ECG parameters to assess severe lesions was created.The joint incremental value of ECG parameters and the area under the ROC curve for assessing severe lesions were calculated.Results The patients in the severe lesion group were elder in age and they showed significantly higher rates in creatine kinase isoenzyme,amino-terminal brain natriuretic peptide precursor,QRS time frame,frontal QRS-T pinch angle,smoking,hypertension,diabetes mellitus,pathologic Q waves,left ventricular hyper voltage,fragmented QRS waves,and significantly lower rates in low HDL cholesterol and ejection fraction,as compared to the non-severe lesion group(all P<0.05).Logistic regression analysis showed that pathological Q waves(OR=3.71,95%CI:1.93～7.15,P<0.001),left ventricular hyper voltage(OR=5.05,95%CI:1.66～15.41,P=0.004),fragmented QRS waves(OR=2.17,95%CI:1.14～4.11,P=0.018),and frontal QRS-T pinch angle(OR=1.01,95%CI:1.00～1.02,P=0.023)were the factors for assessing severe lesions.The incremental value of combined ECG parameters for severe lesions:C-statistic 0.09(95%CI:0.02～0.16,P=0.009),NRI 0.37(95%CI:0.20～0.55,P<0.001),and IDI 0.12(95%CI:0.08～0.17,P<0.001).The ROC curves showed an AUC of 0.79(95%CI:0.74～0.84,P<0.001),a sensitivity of 63.41%,and a specificity of 85.89%for the combined assessment of severe lesions by ECG parameters.Conclusion The combined observations of electrocardiographic parameters such as pathologic Q waves,left ventricular hyper voltage,fragmented QRS waves,and frontal QRS-T pinch angle have an affirmativeclinical value in the assessment of severe lesions.