Comparison of electrocardiogram and vectorcardiogram and results of coronary angiography

AIM:To explore the value of electrocardiogram (ECG) and vectorcardiogram (VCG) in diagnosing coronary artery lesions by comparing the variations of ECG and VCG with the results of coronary angiography (CAG). METHODS: A total of 108 patients clinically diagnosed with coronary heart disease were recruited from January 2008 to December 2009. Routine ECG and VCG were performed followed by CAG within 1 week. Above results were evaluated by their respective diagnostic criteria. CAG was taken as the diagnostic standard for coronary heart disease and relevant indexes were calculated and evaluated by fourfold table method. RESULTS: Sensitivity, specificity and accuracy of VCG were higher than those of ECG (P<0.05 or P<0.01). For intergroup comparison, the positive rate of VCG was significantly higher than that of ECG in the single- or double-vessel lesions (P<0.05), but no statistical significance was observed in left main-vessel or three-vessel lesions. The positive rate of ECG was significantly higher in left main-vessel or three-vessel lesions than in the single- or double-vessel lesions (P<0.05 or P<0.01) and the positive rate of VCG was significantly higher in left main- or three-vessel lesions than in single-vessel lesions (P<0.05). But no statistical significance was seen between left main-vessel or three-vessel lesions and double-vessel lesions. The positive rate of VCG was significantly higher than ECG in coronary artery stenosis ranging from 50 to 69% (P<0.05), but no statistical significance in other groups. For intra-group comparison, the positive rate of ECG was significantly higher in coronary artery stenosis (90%) than that in coronary artery stenosis ranging from 50 to 69% and 70 to 89% (P<0.05 or P<0.01). The positive rate of VCG was significantly higher in coronary artery stenosis 90% than that in coronary artery stenosis ranging from 50 to 69% (P<0.01), but no statistical significance was found in other subgroups. CONCLUSION: The value of VCG is significantly higher than that of ECG in the diagnosis of coronary artery disease.