Comparison of electrocardiographic and left ventricular functional changes during exercise.

Abstract
The diagnostic accuracy of the Bruce multistage exercise treadmill test (ETT) and changes in left ventricular function assessed by radionuclide angiocardiography (RNA) during rest and maximal exercise were compared in 72 patients who underwent coronary arteriography for evaluation of chest pain. Significant coronary artery disease was defined as a 75% or greater stenosis of the diameter of any of the 3 major coronary arteries. The coronary arteriographic results were used to categorize each patient according to the number of vessels with a significant lesion. As a result, 15 patients had insignificant disease and 57 had significant lesions of 1 or more coronary arteries. ETT results were defined as positive if ST-segment changes occurred with exercise, negative if ST-segment changes did not occur at target heart rate and indeterminate if ST-segment abnormalities existed at rest or if no ST-segment changes developed at a heart rate below the target heart rate. Abnormal changes in left ventricular function by RNA were an exercise-induced wall motion abnormality, a less than 5% increase in ejection fraction and a greater than 25% increase in end-diastolic volume and an increase in end-systolic volume with exercise. RNA results were normal in 11 of 15 patients with insignificant disease and abnormal in 4, all of whom had 50% lesions of a major coronary artery. In this group, ETT results were indeterminate in 7 patients, negative in 6 and positive in 2. In the 57 patients with significant coronary disease, RNA results were abnormal in 55 and normal in 2. ETT results were indeterminate in 12 patients, negative in 9 and positive in 36. RNA had a sensitivity of 97% and a specificity of 73% for the 72 patients. ETT had a sensitivity of 80% and a specificity of 66% for the 53 patients with adequate studies. Exercise-induced changes in left ventricular function defined by RNA apparently have greater diagnostic accuracy than the ST-segment response during ETT in the patient population studied.

This publication has 19 references indexed in Scilit: