Observations on the Hemodynamic Effects of Experimental Internal Mammary Artery Ligation

Although the surgical treatment of congenital and rheumatic heart disease has undergone remarkable expansion and refinement during the past 12 years, progress in the surgical therapy of arteriosclerotic heart disease has remained relatively stationary. The employment of at least 15 different surgical procedures for the treatment of this condition bears witness to the inconclusive results.^1-9

This presentation concerns an attempt to study basic hemodynamic principles as they apply to experimental internal mammary artery ligation. Experimental methods were developed to gain information concerning the pressure and flow relationships in the internal mammary-pericardiophrenic artery system which would demonstrate whether the surgical procedure under investigation could logically be expected to increase blood flow through the desired channels. The existence of these channels has been known for many years and has been confirmed by injection studies.⁸ Only recently has an attempt been made to utilize them as collateral routes for the purpose