Non-invasive quantification of exercise-induced changes in regional left ventricular function in normals and patients with one vessel coronary artery disease using radionuclide ventriculography
To quantitate changes in regional left ventricular function induced by ischemia or scar, rest and exercise equilibrium radionuclide studies of 26 patients with one vessel coronary artery disease and 12 normal individuals were analysed with a new method for regional ejection fraction determination. A computer algorithm provided observer-independent segmental analysis from a centre of gravity of the left ventricular activity at end-diastole (left anterior oblique projection). Special segments were assigned for anteroseptal, inferoapical and posterolateral areas corresponding to the three main coronary arteries. Reproducibility using an unchanged camera positioning was excellent even for 2 min acquisition studies (r=0.93) and still good after repositioning (r=0.80 to 0.87). In normal areas, regional ejection fraction increased or showed no change during exercise. In contrast, it decreased significantly in regions supplied by stenosed coronary arteries (ischemia) and remained depressed in scar zones. The method proved to be valid for regional changes induced by left anterior descending and left circumflex coronary obstructions, but less for right coronary artery lesions. Global ejection fraction reflected a sum of all regional changes implying that regional analysis should be more sensitive in detecting coronary artery diseas
