Comparison And Analysis Of The Results Between Electrocardiography And Coronary Angiography

Objective The goal of this study was to discuss the value of electrocardiography in diagnosis of coronary artery diseases and in predicting the site of IRA in the acute myocardial infarction by comparing and analyzing the results between electrocardiography and coronary angiography.Methods 1628 patients who accepted CAG examinations in the TEDA international cardiovascular hospital from November 2003 to November 2005 were selected. At the same time, the results of ECG and UCG were recorded. The electrocardiographic changes were compared and analyzed with coronary angiography.Results 1. Double-vessel disease (odds ratio 1.986, 95% confidence interval 1.181 to 3.342, P< 0.01) was positive influence factor of ST-T changes;LVEF (odds ratio 0.951, 95% confidence interval 0.936 to 0.966, P< 0.01) was negative influence factor. 2. Normal ECG proportion was 38.9% in the patients with stenosis >50% of the LM, 33.3% in the patients with three-vessel disease, 38.6% with double-vessel disease, 57.7% with single-vessel disease and 67.5% without stenosis. Abnormal ST-T changes were higher in the group with stenosis >70% than the group with stenosis 50%-70%.Like this, they were higher in the group with stenosis >70% than the group without stenosis (P<0.01) .They had not statistically significant differences between the group with 50%-70% and without stenosis (P>0.05) . ST-T changes were different between single- and double-vessel disease,as the same as, betweensingle- and three-vessel disease (P<0.01) .On the contrary, they were similar between double- and three- vessel disease( P>0.05).3. Diagnostic tests between ST-T changes and the diseased vessels showed that ECG ( + ) > ST-T ( + ) and ST ( + ) were more sensitive for the group with stenosis >70% than >50%, specificities were similar.4. Kappa statistics between ECG and CAG for the group with and without chest pain (K=0.178, P<0.05;K=0.152, PO.01) had statistically significant difference respectively, but agreement ( K<0.40 ) was poor.Sensitivity (54.9%vs48.9%) was greater for the group with chest pain than without chest pain, specificity was similar (67.9%vs67.3%) . 5. The group excluding ST segment elevation had lower sensitivity and accuracy compared to the group excluding secondary ST-T changes.The differences were no longer significant for ST segment depression in different degree (x2=3.652, P=0.056) and >5 leads (x2=6.897, P>0.05) to evaluate the number of the diseased vessels. 6. If the lead Viand V3 was the center of the ST segment elevation respectively, Coincidence was 71.9%and 71.4 % in predicting the proximal and the middle.Coincidence in predicting the LAD disease with ST segment elevation in anterior wall was 84%, in predicting the RCA disease in inferior wall was 90%. The proximal lesions were often seen in the LAD than RCA. Lateral AMI was less compared with others. 7. Proportion of three-vessel disease was higher than double- and single-vessel disease for RSTD of the anterior wall in AMI (x2= 14.557, P<0.01). If the lead V3> V^ V5> V6 or avL was the center of the greatest depression respectively, it probably indicated the three-vessel disease;The lead V2 as the center of the greatest depression was a clue of single-vessel disease. 8. LVEF was obviously higher for the group without Q waves than with Q waves (57.25±8.18vs51.87±10.37);The group with the number of Q waves<4 compared with >4 was the same thing (54.61±8.85vs 43.93±10.55) .9. QS wave inthe lead Vi supported the site of lesion in the LAD (￡2=65.577, PO.01) . ST segment depression in the lead avL for the patients with inferior AMI showed that IRA was RCA (y?=9.677, PO.01) .The degree of ST segment elevation in the lead III>II showed that IRA was RCA (%2=5.207, PO.05) too.Conclusions It was many factors that influenced ST-T changes. Double-vessel disease was major positive influence factor;LVEF was an important negative influence factor. The ECG excluding secondary ST-T changes had low sensitivity > specificity and accuracy for diseased vessels,but agreement with heavy was higher than light stenosis, with multi- was higher than single-vessel disease. The results between ECG and CAG had poor agreement, but in some sense, the grade of diseased vessels could be reflected. Accuracy of consecutive ST segment depression for the ECG excluding ST segment elevation was low and had a low significance in predicting the site of the anatomic lesion of the coronary artery. In AMI, the ST segment elevation in the lead V2 and V3 as the center respectively is a clue in predicting the proximal and the middle of LAD. Coincidences in predicting LAD disease with ST segment elevation in anterior wall and RCA disease in inferior wall were high. RSTD in anterior wall was correlative with three-vessel disease. LVEF decreased in the group with Q-waves and the number of Q-waves >4. QS-wave in the lead Vj was significant for the LAD disease.ST segment depression in the lead avL and the degree of ST segment elevation in the lead III>II in inferior AMI were referenced for the RCA disease.