ATHEROSCLEROSIS OF THE INFERIOR EPIGASTRIC AND INTERNAL MAMMARY ARTERIES

Atherosclerosis of the inferior epigastric artery (IEA) and the intern al mammary artery (IMA) was evaluated in 21 patients with coronary hea rt disease. Both arteries were used simultaneously in coronary artery bypass grafting. Histologic samples were obtained from the proximal an d distal segments of IEA and from the distal segment of IMA. Morpholog ic findings in regard to atherosclerosis were classified semiquantitat ively as normal (0), or luminal narrowing < 25% (1), 25-50% (2) or > 5 0% (3), or as overt atherosclerosis and calcification (4). Atheroscler osis was absent or minimal (1) in distal samples from both arteries. O nly one IMA showed moderate (2) luminal atherosclerotic obstruction. T wo samples from proximal IEA showed moderate (2) or severe (4) atheros clerotic changes which limited their use as free grafts. These finding s suggest that atherosclerosis is minimal and comparable in distal IEA and IMA in their natural environments even in patients with coronary heart disease. The long-term effect of aortic pressure on free IEA gra ft is still unclear.