Regional ejection fraction during exercise: a quantitative measurement to localize coronary artery stenoses in patients with symptomatic or silent myocardial ischemia.

To determine the ability of quantitative radionuclide ventriculography to localize coronary artery stenoses in patients with angina and silent myocardial ischemia, the authors studied changes in regional ejection fractions produced by supine bicycle exercise in 49 patients, 16 of whom had silent myocardial ischemia. For example, in 35 patients with 70 per cent or greater stenoses of the left anterior descending and/or left main coronary artery, anteroseptal regional ejection fraction fell from 55 +/- 3 per cent at rest to 50 +/- 4 per cent with exercise (p less than 0.05). In 14 patients with lesser or no stenoses of the left anterior descending and/or left main coronary artery, anteroseptal regional ejection fraction increased from 62 +/- 4 per cent at rest to 67 +/- 5 per cent during exercise (p less than 0.05). Similar findings were obtained in patients with 70 per cent or greater stenoses of the left circumflex and/or right coronary artery in whom inferoposterior regional ejection fraction was measured and compared with that in patients with lesser or no stenoses in these vessels. Thus, evaluation of regional ejection fraction allowed the localization of coronary artery stenoses in coronary patients whether or not their ischemia was accompanied by pain.