Elimination of variable vasomotor tone in studies with repeated quantitative coronary angiography
Abstract
In quantitative coronary angiographic studies, unintentional changes of coronary vasomotor tone may have a significant influence on the coronary artery diameters, thereby increasing the variability in the measurements. To obtain objective data on these measurement variabilities, two protocols were designed to assess the influences of ionic and nonionic radiographic contrast media on the mean diameters of angiographically normal coronary arteries. The vessel sizes were determined with the CAAS using automated edge detection techniques. In 21 patients (study no. I), coronary angiograms were taken in identical angiographic projections before (control), and immediately following several (at average 7) subsequent diagnostic dye injections administered over a period of about 7 min. The ionic contrast agent diatrizoate 76% induced a coronary dilation of 19 +/- 7% (mean +/- s.d., p less than 0.001; n = 10); the nonionic agent iopromide 370 increased the coronary artery diameters by only 6 +/- 4% (p less than 0.01; n = 11). In another 11 patients (study no. II) coronary angiograms were obtained using the nonionic contrast medium iopamidol 300 at 5, 8, 10 and 11 min after the control acquisition; this protocol was repeated in the same pa...Continue Reading
References
Citations
Related Concepts
Related Feeds
Antianginal Drugs: Mechanisms of Action
Antianginal drugs, including nitrates, beta-blockers, and calcium channel blockers, are used in the treatment of angina pectoris. Here is the latest research on their use and their mechanism of action.