The value and accuracy of intracoronary electrocardiogram in the diagnosis of myocardial ischemia in coronary heart disease.

BACKGROUND Although intracoronary electrocardiography (IC-ECG) offers direct electrophysiological insights into myocardial ischemia caused by insufficient coronary blood supply, compared to common diagnostic methods like electrocardiography (ECG), it lacks widespread adoption and robust clinical research. OBJECTIVE To analyze the value and accuracy of intracoronary electrocardiogram in myocardial ischemia diagnosis in coronary heart disease patients. METHODS Three hundred patients treated at our hospital were included in the study. Patients were categorized into non-ischemic group A (Fraction Flow Reserve [FFR] > 0.8) and ischemic group B (FFR < 0.75) based on FFR examination results. Both groups underwent IC-ECG examination. The ischemic group received percutaneous coronary intervention (PCI) treatment followed by another FFR examination, dividing them into non-ischemic subgroup B1 (FFR > 0.8) and ischemic subgroup B2 (FFR < 0.75). Both subgroups underwent IC-ECG examination. Receiver operating curves were constructed using FFR to assess the clinical utility of different IC-ECG parameters. RESULTS Group A patients showed a significant decrease in ST-segment shift at J-point, ST-segment integral, T-peak, T-wave integral, and T-peak to end-time, while the Corrected Q-T interval (QTc-time) was significantly higher in the B group (p< 0.05). The parameters, including ST-segment shift at J-point, ST-segment integral, T-wave integral, T-peak, T-peak to end-time, and QTc-time, were found to have clinical significance in predicting the occurrence of myocardial ischemia (p< 0.05). CONCLUSION Intracoronary electrocardiogram QT interval dispersion and Q-T peak (QTp) interval dispersion have a high diagnostic accuracy for myocardial ischemia in coronary heart disease.