2007 Volume 5 Issue 1 Pages 21-27
Background. There have only been a few studies that visualized the human coronary tree continuously from coronary arteries to capillaries in the clinical setting. The purpose of this study was to visualize the human coronary tree non-invasively with myocardial contrast echocardiography (MCE) by changing frame rates.
Methods. MCE was performed intravenously using TMLevovist. Study population consisted of 20 patients with ischemic heart disease. We performed 3 kinds of MCE: intermittent, semi-real, and real-time harmonic imaging.
Results. 1. Myocardial blood flow velocity and volume were obtained from the time-intensity replenishment curve with intermittent imaging. Curve fitting was possible in 75% of the targeted region of interest. 2. Semi-real-time perfusion image was obtained with a frame rate of 5/sec. We observed a cyclic variation of echo-intensity in one cardiac cycle in only viable region (Peak subtracted signal intensity: 53±29 in end-diastole and 33±27 in end-systole, p<0.05). This phenomenon may result from the compression of arterioles according to cardiac beat. 3. Real-time perfusion image was obtained at a rate of 26 frames/sec. We observed line-form small artery flows in 80 % of the viable area.
Conclusions. Thus, coronary tree following major epicardial coronary arteries was visualized non-invasively from the small artery to the capillary bed with 3-staged intravenous-MCE in the clinical setting.
