In patients who underwent coronary bypass surgery, the incidence of AMI and mortality was similar in both groups. According to Granborg et al, the long-term prognosis of isolated ischemic T wave changes regardless of whether they represent NQMI or unstable angina is poor. During 31 month follow-up, 17 percent of patients developed AMI and 24 percent died.
The incidence of AMI and mortality in patients with unstable angina is relatively low, and there is no benefit from early coronary bypass surgery. However, there are patients with unstable angina who have a higher morbidity and mortality and can be identified by typical ECG changes. ventolin inhaler
First, Gorgels et al showed that ST segment depression in more than eight leads and ST segment elevation in aVR should raise the possibility of left main disease or severe proximal three vessel disease. Consistent with this observation is the ECG in Figure 1 which was recorded in a patient during severe rest pain in whom coronary angiography showed 90 percent proximal left anterior descending artery and left circumflex coronary artery stenosis (left main equivalent).
Figure 1. Diffuse ST segment depression ranging from 0.5. to 4.0 nun in all except lead aVL and V, and 1 mm ST segment elevation in lead aV’R. This ECG was recorded during severe substernal chest pain in a patient with 90 percent proximal LAD and left circumflex coronary artery obstruction (left main equivalent).