1 Regional myocardial flow Radioactive potassium study From the Department of Medicine, Case Western Reserve University, and University Hospitals of Cleveland, Cleveland, Ohio.
A new method to determine myocardial blood distribution was used to study a patient with a recent large transmural anterior myocardial infarct. The method consisted of injecting 43potassium into a peripheral arm vein and recording the radioactivity over the chest with a scintillation (Anger) camera. Elimination of noncardiac radioactivity in the analysis of data was accomplished by recording the rapid passage of injected 99mtechnetium through the heart. The cardiac deposition of the potassium was visualized by identifying the contour of the heart from the technetium scan. In this patient deposition of 43potassium was markedly reduced in the septal region of the myocardium. This correlated well with the ischemic area suggested by coronary angiography, which demonstrated proximal occlusion of the left anterior descending coronary artery and absence of obstructive disease in the other coronary arteries. Intracoronary artery injection of 43K gave confirmation of decreased deposition in the same area. This method should prove helpful in the study of certain clinical problems, such as the evaluation of the patency of coronary artery bypass grafts.
Submitted on July 25, 1972
© 1973 American Heart Association, Inc.
Identification of Ischemic Area of Left Ventricle by Visualization of 43K Myocardial Deposition
Key Words: Myocardial blood distribution • Cardiac imaging
Accepted on November 15, 1972