Relation between coronary anatomy and serial changes in left ventricular function on exercise: a study using first pass radionuclide angiography with gold-195m.
Serial changes in left ventricular function on exercise were assessed by first pass radionuclide angiography with gold-195m (half life 30.5 s) in 25 men with known coronary anatomy. In the seven patients with three vessel disease, abnormalities of global left ventricular function and regional wall motion occurred earlier during exercise, were of greater extent at peak exercise, and persisted longer after exercise than in the 11 patients with one and two vessel disease or the seven with normal coronary arteries. Although there were significant differences between the groups in absolute change in ejection fraction and the rate of change in ejection fraction related to exercise duration and heart rate, a considerable overlap of values between groups precluded the accurate prediction of coronary anatomy in individuals. These data suggest that the amount of myocardium at risk from ischaemia in some patients with one and two vessel disease may resemble that in patients with three vessel disease. This study shows that an anatomical classification based solely on the number of diseased vessels will not predict the extent of the impairment of left ventricular function on exercise.