Further Observations on Aorta to Coronary Sinus Anastomosis of Beck in Dogs. ∗

Abstract

Summary

1. Measurements of retrograde circumflex artery flow, peripheral coronary artery pressure, and electrocardiographic changes induced by circumflex artery ligation were evaluated in an additional 5 Beck #2 operated dogs. 2. Twenty-six Beck #2 operated dogs studied from 4 weeks to one year after the second stage of the operation have been compared with: 1) 41 control dogs, 2) sham Beck #2 operated dogs, 3) defibrillated dogs, and 4) Beck #2 operated dogs 3 months after ligation of the graft. 3. Beck #2 operation results in a significant development of intercoronary arterial communications which persist for at least one year in the presence of a functioning graft and for at least 3 months after ligation of the graft. 4. Sham Beck #2 operated dogs develop intercoronary arterial communications which is in contrast to the lack of such communications following ventricular defibrillation. 5. Further substantiation is provided for previous evidence that in a majority of the Beck #2 operated dogs both functional and anatomical contacts between the perfused venous system and a capillary bed are eventually lost. Consequently earlier conclusions are supported that after about 5 weeks the Beck #2 operation protects normal dogs from the effects of coronary artery ligation by means of intercoronary arterial communications.