RELATIONSHIP BETWEEN NORMALIZATION OF NEGATIVE T-WAVE ON EXERCISE ECGAND RESIDUAL MYOCARDIAL VIABILITY IN PATIENTS WITH PREVIOUS MYOCARDIAL-INFARCTION AND NO POSTINFARCTION ANGINA

The usefulness of normalization of negative T waves in exercise ECG wa s investigated as an index of myocardial viability in patients with pr evious myocardial infarction with no symptoms or ischemic ST-segment c hange during exercise test. A total of 39 patients, 20 with T-wave nor malization (POS group) and 19 without T-wave normalization (NEG group) on exercise ECG, were studied. Myocardial viability was evaluated by thallium-201 single-photon emission computed tomography (SPECT) during exercise or at rest. We also assessed left ventricular ejection fract ion (LVEF) by contrast ventriculography before (n=39) and after percut aneous transluminal coronary angioplasty (PTCA) (n=17). SPECT detected myocardial viability in 16 (80%) of the 20 patients in the POS group and in 4 (21%) of the 19 patients in the NEG group (p<0.01). LVEF incr eased after successful PTCA in the POS group (from 53+/-13% to 63+/-8% , p<0.025), but fell in the NEG group (from 57+/-10% to 51+/-8%). It i s concluded that normalization of negative T waves on exercise ECG is a useful, simple index of myocardial viability in patients with previo us myocardial infarction with no symptoms or ischemic ST-segment chang e during exercise testing.