The Journal of Thoracic and Cardiovascular Surgery, Vol 78, 68-73, Copyright © 1979 by The American Association for Thoracic Surgery and The Western Thoracic Surgical Association
Preoperative and postoperative technetium-99m pyrophosphate myocardial scintigraphy in the assessment of operative infarction in coronary artery surgery
J Hung, DT Kelly, AF McLaughlin, RF Uren and DK Baird
The incidence of operative myocardial infarction was assessed by
electrocardiogram (ECG) and technetium-99m pyrophosphate (99mTc-PyP)
myocardial scintigrams in 89 consecutive patients undergoing coronary
artery bypass grafting (CABG). Myocardial scintigrams were performed on the
day before operation and repeated 2 to 3 days postoperatively. All patients
survived operation, with three in-hospital deaths not related to myocardial
infarction (mortality rate 3 percent). Operative infarction was assessed to
have occurred in four of 89 patients (4 percent). Two had new Q waves and
positive scintigrams; one, major ST-T wave changes and a positive
scintigram; and the fourth, new Q waves without a positive scintigram.
Three further patients (3 percent) had Q waves and positive scintigrams
postoperatively, but myocardial infarction was evolving before anesthesia
and operation. Twenty-seven of 89 patients (30 percent) were found to have
abnormal scintigrams preoperatively. In two patients, both operated upon
with evolving myocardial infarction, the scintigram was worse
postoperatively. In 13 patients the scintigram was improved after
operation. In 12 patients (13 percent) the abnormal preoperative scintigram
was unchanged after operation. Preoperative and postoperative myocardial
scintigrams and ECG's must be compared to assess the incidence of operative
myocardial infarction in patients undergoing CABG.