Ejection fraction response to exercise in patients with chest pain, coronary artery disease and normal resting...

We studied the ejection fraction (EF) response to upright exercise using first-pass radionuclide angiography (RNA) in 281 patients with chest pain, significant coronary artery disease and normal resting ventricular function. A wide range of resting function (heart rate and EF) and exercise function (heart rate, EF and peak work load) was measured in this population. The EF response to exercise (delta EF) varied widely, ranging from a decrease of 36% to an increase of 26%. Twenty-eight clinical, catheterization and RNA variables were examined to determine their relationship to delta EF. Considered individually, the variables showing the strongest relationship were resting pulse pressure, positive exercise ECG changes and adequate exercise. Multivariable analysis identified resting pulse pressure, adequate exercise, resting EF, the change in end-diastolic volume index with exercise, positive exercise ECG changes and, to a lesser degree, the number of diseased vessels as variables that were significant independent predictors of delta EF. These observations indicate that delta EF is a complex response that is influenced by many pathophysiologic variables in the presence of coronary artery disease. Several of these variables are not related to the extent of coronary artery disease.