A quantitative approach to collateral and antegrade flows after coronary occlusion.

&HEEL, KONRAD Mr., MANUEL BANET, COBERN OTT, AND PATRICK H. LEHAN. A quantitative approach to collateral and antegrade flows after coronary occlusion. Am. J. Physiol. 222(3): 687-694. 1972.-In an isolated dog heart preparation, the circumflex, anterior descending, and right coronary arteries were simultaneously perfused and blood flow was monitored by electromagnetic flow probes. The retrograde-flow method was used to determine the potential collateral flow. In a group of nine (control) animals, the collateral flows as well as the antegrade flows were measured during an acute occlusion of one of the coronary arteries. In a second group of 16 animals (experimental), the potential collateral as well as the antegrade flows were determined after an Ameroid occluder had been placed on one of the left coronary arteries or the right coronary artery for several months. The antegrade flow of the occluded vessel was measured by cannulating the vessel just distal to the occluder. The collateral conductance in the experimental group increased up to loo-fold in comparison to the control group. After a circumflex or anterior descending occlusion, the lowest collateral resistance was observed between the circumflex and anterior descending coronary arteries, while the right coronary artery favored collateral development to the circumflex rather than the anterior descending coronary artery. Antegrade flows distal to the occlusion in some cases decreased relative to control flows. Concomitantly, the flow in another coronary artery seems to increase. After a 4-month occlusion of the circumflex artery, the collateral resistance was almost 3 times smaller than the peripheral resistance of the artery supplied by the collaterals. After several months of coronary occlusion, the naturally developing collaterals seem to be able to supply a more than basal need to the o&ded vessel.