부산대학교 도서관

One method of assessing the health of the coronary arteries (the arteries that deliver blood to the heart tissue itself) is a noninvasive approach called Doppler echocardiography, an ultrasound technique that provides an image of the beating heart and its blood flow. Since ischemia (decreased blood flow) is a consequence of coronary artery disease, testing should determine if blood flow in these arteries is normal. It is possible that injection of an agent that causes vasodilation (enlargement of the blood vessels), combined with Doppler echocardiography, would constitute a useful diagnostic approach. This method was tested in 42 subjects who underwent diagnostic coronary angiography (injection of a dye into the coronary arteries, followed by X-ray pictures of the dye in the vessels) because they had experienced a chest pain syndrome. Thirteen patients had normal coronary arteries and constituted the control group; the rest had coronary artery disease of at least one coronary artery. All patients received dipyridamole (a vasodilator) intravenously and heart rate, blood pressure, and electrocardiographic variables were monitored continuously. Doppler and two-dimensional echocardiography (an ultrasound technique that allows measurement of other aspects of coronary function) were also performed, as were measurements of hemodynamic variables such as pressure in the chambers of the heart. The results showed that measurements obtained with Doppler echocardiography increased for control subjects after dipyramidole was administered, but certain variables did not change in patients with coronary artery disease. The measures that remained constant were peak flow velocity (velocity of blood flow at the point in the cycle of maximum output), flow velocity integral, and stroke volume (the amount of blood pumped with one contraction). Heart rate and most other measures remained the same in both groups before and after dipyridamole. The changes noted in patients with coronary artery disease appear to be the result of ischemia of the heart muscle. It therefore appears that Doppler echocardiography can be used to distinguish certain patients with heart disease from normal subjects. Limitations of the method are discussed. (Consumer Summary produced by Reliance Medical Information, Inc.)
Two-dimensional and Doppler echocardiographic studies and a hemodynamic investigation were performed during dipyridamole testing in 42 subjects (13 control subjects and 29 patients with coronary artery disease [CAD]), to evaluate the ability of dipyridamole Doppler echocardlography in identifying patients with ischemic left ventricular dysfunction. in the control group, after dipyridamole infusion, Doppler-derived parameters increased significantly from baseline (p (Am J Cardiol 1990;65:829-834)