The Journal of Thoracic and Cardiovascular Surgery, Vol 70, 89-99, Copyright © 1975 by The American Association for Thoracic Surgery and The Western Thoracic Surgical Association
The fate of internal mammary arterial implants and bypass conduits for myocardial revascularization. Experimental angiographic, histologic, and ultrastructural observations
MH Mullerworth, FJ Daniel and JT Lie
Experimental angiographic, histologic, and ultrastructural observations
were obtained from dogs to determine the fate of internal mammary artery
(IMA) implants and aorta-coronary bypass (ACB) conduits in the 3 month
postoperative period. Angiographic implant patency and evidence of implants
forming collaterals with the coronary circulation did not accurately
reflect anatomic luminal narrowing. Subendothelial fibrocellular
proliferation similar to that described in saphenous vein grafts occurred
with regularity in all IMA implants and ACB conduits. The intimal changes
were much more severe in the IMA implants as compared to the ACB conduits:
There was 25 to 95 per cent liminal narrowing in the IMA implants, whereas
the ACB conduits rarely showed greater than 25 per cent luminal narrowing.
Both reduced flow and surgical trauma appeared to be influential
determining factors of the intimal proliferative process, whereas
devascularization alone seemed less important.