The application of coronary CT angiography combined with dynamic electrocardiogram in the diagnosis of myocardial ischemia in coronary heart disease

Objective This study aims to analyze the diagnostic methods for myocardial ischemia in coronary heart disease and compare the diagnostic performance of coronary CT angiography (CCTA), dynamic electrocardiogram (DCG), and CCTA-DCG. Methods This study retrospectively selected 300 patients who underwent CCTA and DCG examinations due to chest pain and suspected coronary heart disease in a hospital in Shanghai from January 2023 to June 2025. These patients were further divided into the ischemia group and the non-ischemia group based on whether they were diagnosed with myocardial ischemia in coronary heart disease. The patients' routine and clinical data were selected. Subsequently, the diagnostic performance was analyzed, and its accuracy was evaluated through the receiver operating characteristic (ROC) curve. Results In the ischemia group, the CCTA parameters NCPV, CPV, Agaston score, and TPV were all higher than those in the non-ischemia group ( P < 0.05). The DCG parameters, triangular index, and heart rate deceleration force in the ischemia group were lower than those in the non-ischemia group, while the LF/HF ratio was higher ( P < 0.05). The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of CCTA diagnosis were 90.66%, 70.34%, 82.50%, 83.00% and 82.67% respectively, while those of DCG diagnosis were 78.02%, 52.54%, 71.72%, 60.78% and 68.00% respectively. The combined diagnosis of CCTA-DCG was 96.15%, 91.53%, 94.59%, 93.91% and 94.33% respectively. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of CCTA-DCG diagnosis were significantly higher than those of CCTA and DCG diagnosis ( P < 0.05). The AUC value was 0.966 (95% CI: 0.943–0.989). Conclusion The combination of CCTA and DCG has high accuracy in diagnosing myocardial ischemia in coronary heart disease, which is of great significance for the clinical diagnosis of myocardial ischemia in coronary heart disease.