Copyright © 1988 by the European Society of Cardiology.
© 1988 The European Society of Cardiology
Is the rate of disappearance of echo contrast from the interventricular septum a measure of left anterior descending coronary artery stenosis?
Thoraxcenter, Erasmus University Rotterdam Rotterdam, The Netherlands
Received 11 September 1987; revised 17 March 1988; .
Address for Correspondence: Folkert J. Ten Cate. M.D., Erasmus University Rotterdam, Department of Cardiovascular Research, 23rd floor, P.O. Box 1738, 3000 DR Rotterdam, The Netherlands.
Abstract
Although myocardial contrast echo been used recently in human studies, no study is available at the present time which relates contrast echo findings to the degree of coronary artery stenosis. The present study is the first attempt to determine whether a quantitative relationship exists between regional myocardial echo contrast disappearance rate (washout) and the severity of coronary artery stenosis.
Manual injection of sonicated iopamidol (Iopamiro® 370) into the left main coronary artery with simultaneous cross-sectional echo registration provided the myocardial echo-contrast images. From the digitized images, an echo contrast timeintensity curve was constructed for the proximal basal interventricular septum (region I) and the mid-distal portion of the inter ventricular septum (region II). From these curves, T50 was calculated after Fourier transformation and mono-exponential curve fitting. The percentage stenosis area (%A) of the left descending coronary artery (LAD) was calculated from routine coronary arteriograms using a computer-based system. Thirty patients (22 men, 8 women; mean age 58±10 years) were included in the study. Group I (n=7) had normal LAD, group II (n=18) had LAD stenosis of varying degrees. Five patients were not suitable for quantitative evaluation. A curvilinear relation was found between T50 and %A. (T50=3.0 x e0.01%A; r=0.78; P<0.05).
Patients with asynergy had significantly longer T50 (8.2±2.5 s) than did patients without asynergy (4.2±1.5 s) (P<0.05). All patients with > 75% LAD % A had prolonged T50. T50 might be useful index for studying regional myocardial perfusion during cardiac catherterization.
Key Words: Myocardial contrast echo coronary artery stenosis T50 myocardial blood flow.