Radiology, Vol 136, 191-195, Copyright © 1980 by Radiological Society of North America
Sequential thallium-201 myocardial scintigraphy after acute infarction in man: comparison to creatine kinase-MB release pattern
JW Fletcher, HS Mueller and PS Rao
Three sequential Tl-201 myocardial perfusion studies were performed in 21
patients (18 men, 3 women) with first acute transmural myocardial
infarction. The Tl-201 image defect size was determined with a
semiquantitative visual scoring method and temporal changes in image defect
size were compared to CK-MB infarct size and enzymatic evidence of
progressive myocardial necrosis and infarct extension. Progressive
decreases in Tl-201 image defect size were observed and the visual score in
all 21 patients decreased significantly from 6.5 +/- 3.7 (mean +/- SD) on
day 1 to 4.9 +/- 3.5 on day 12. Eleven patients without evidence of infarct
extension had significantly lower infarct size, a significant decrease in
visual score by the 12th day and had significantly smaller Tl-201 defects
at all three study times compared to 10 patients with infarct extension.
Seven of 10 (70%) with extension had an initial score greater than or equal
to 7 compared to only 2/11 (18%) without extension. The temporal behavior
of Tl-201 image defects is related to the size of the infarction and
presence or absence of extension. Sequential studies comparing early
initial and subsequent defect size may assist in evaluating the behavior of
ischemic and infarcted myocardium in the postinfarction period.
