ABSTRACT
The resting electrocardiography performed routinely in the clinical field is a useful method for the diagnosis of ischemic heart diasese and for predicting its prognosis. There have been reports about angina patients with symmetric T wave inversion in the precordial leads on the resting electrocardiogram(EGC) who usually showed stenotic lesions of left anterior descending coronary artery and with poor prognosis. However, we have had no studies on this subject in Korea. The authors conducted retrospectively a comparative study on the patients with angina pectoris in the Yonsei University Severance hospital from jan. 1980 to Dec. 1989. We set two groups for comparison; one group consisted of 89 patients who had more than 50% stenosis in luminal diameter of coronary artery on coronary angiogram and persistent symmetric T wave inversion in the precordial leads(T negaive group) ; the other group in cluded 132 patients who had normal ECG but significant stenosis of the coronary arteries(T positive group). We compared these two groups in clinical and coronary angiographic findings and evaluated the changes of T wave after percutaneous transluminal coronary angioplasty (PTCA) and medical treatment in the T negative group. 1) The mean age of the T nagative group was 56.4+/-12.9 years, and the male to female ratio was 2.3 : 1. In the T positive group, the mean age was 54.4+/-8.8 years, and the male to female ratio was 3.1 : 1. There was a relatively high occurrence rate in females in the T negative group, but this was not statistically significant. The duration of angina was 5.7+/-11.2 months in the T negative group, and 9.0+/-13.8 months in the T positive group, and relatively short in the T negative group. There was no difference in the risk factors between these two groups except for a slightly higher level of serum cholesterol in the T positive group than the T negative group(187.4+/-33.5mg/dl v/s/ 199.9+/-49.2mg/dl, p<0.05). 2) The extent of coronary artery disease in the T negative group was 3 cases of left main coronary artery disease(3.3%), 54 cases of one vessel disease(60.7%), 20 cases of two vessel disease(22.5%), 12 cases of three vessel disease(13.5%); in the T positive group, left main coronary artery disease was found in 10 cases(7.5%), on e vessel disease in 71 cases(53.8%), two vessel disease in 29 cases(22.0%), three vessel disease in 22 cases(16.7%). There was no difference in the extent of coronary artery disease between these two groups. 3) The occurrence rate of involvement of left anterior descending artery(LAD) and its branches was 87.9% in the T negative group, and 76.5% in the T positive group, which indicated more frequent involvement of LAD in the T negative group(p<0.05). The mean degree of stenosis of LAD was 79.5+/-17.0% in the T negative group, and 77.0+/-16.2% in the T positive group, but there was no significant difference between the two groups. Those patients with more than 95% stenosis of LAD were 32.9% of the T negative group, 14.3% of the T positve grouup, and the T negative group showed a significantly higher rate than the T positive group(p<0.05). 4) The wall motion abnormalities in the LAD territory were more frequently noted in the T negative group than the T positive group(25.3% v.s. 11.9%, p<0.05). However, upon determining the ejection fraction(68.8+/-12.8% v.s. 71.9+/-11.4%) and left ventricular end diastolic pressure(11.6+/-5.4mmHg v.s. 12.9+/-4.9mmHg), no difference was found. 5) There were no episodes of acute myocardial infarction or hospital death during the admission in either group except for 2 cases of death after coronary artery bypass graft in the T positive group. 6) Although the patients who unerwent PTCA showed more severe stenosis of LAD than those who had medical treatment only in the T negative group(863.8+/-10.9% v.s. 70.8+/-21.4%, p<0.05), there was a higher rate of normalization of T wave inversion in the PTCA group compared with that in the medical treatment gorup(70.8% v.s. 37.0%, p<0.05). The above results suggest that T wave inversion in the precordial leads on the resting ECG in patients with angina pectoris was associated with severe stenosis of LAD and ventricular wall motion abnormalities, and the T wave inversion could be normalized with improvement of myocardial ischemia and the prognosis for such patients was relatively good in appropriate treatments such as PTCA were performed.