Measurement of acute myocardial infarcts in dogs with /sup 99m/Tc-stannous pyrophosphate scintigrams

Myocardial scintigrams using /sup 99m/Tc-stannous pyrophosphate (/sup 99m/Tc-PYP) can be used to measure myocardial infarcts produced in dogs by proximal ligation of the left anterior descending coronary artery. Seven dogs had /sup 99m/Tc-PYP myocardial scintigraphy performed 24 to 32 hr after ligation of the proximal left anterior artery. In each dog the scintigrams showed increased /sup 99m/Tc-PYP uptake in the distribution of the artery. The scintigraphically visible areas of infarction, measured using interactive computer-aided techniques, were compared subsequently with independent histologic measurements of myocardial infarct size. Several methods for using the area measurements to estimate infarct size were treated. The most successful method (r = 0.92, p less than 0.01) assumed a linear relationship between the largest scintigraphic infarct area and the histologically determined infarct weight. The results suggest that /sup 99m/Tc-PYP myocardial scintigrams provide a useful noninvasive method for measuring infarct size in dogs with proximal ligation of the left anterior descending coronary artery