MORPHOMETRIC ANALYSIS OF THE RIGHT GASTROEPIPLOIC ARTERY AND THE INTERNAL MAMMARY ARTERY

Background. The internal mammary artery (IMA) and the right gastroepip loic artery (RGEA) are frequently used as conduits for coronary artery bypass grafting. Methods. Morphometric measurements and histologic ch aracteristics of the RGEA and the IMA were studied in 25 patients unde rgoing coronary artery bypass grafting. Results. External radius was f ound to be more in the IMA (range, 18 to 56 mu m; mean, 39.56 mu m) in comparison with the RGEA (range, 24 to 51 mu m; mean, 32.52 mu m; p < 0.01). There was no significant difference between the vessels in int imal thickness (IMA: 0.0 to 0.25 Crm; mean, 0.05 mu m; RGEA: 0.0 to 0. 28 mu m; mean, 0.09 mu m), internal radius (IMA: 5 to 47 mu m; mean, 2 8.40 mu m; RGEA: 16 to 42 mu m; mean, 23.56 mu m), area of media (IMA: 1,690 to 3,476 mu m(2); mean, 2,777.52 mu m(2); RGEA: 1,659 to 3,600; mean, 3,012.44 mu m(2)), intimal thickening index (IMA: 0.0 to 0.02; mean, 0.01; RGEA: 0.0 to 0.13; mean, 0.01), and medial index (IMA: 0.1 4 to 0.60; mean, 0.36; RGEA: 0.18 to 0.63; mean, 0.39). Histologic exa mination of the RGEA showed more defects in continuity of internal ela stic lamina and rich smooth muscle cells in the media. Conclusions. Th ere was no difference in the morphometric measurements of the IMA and the RGEA except external radius, which was greater for the IMA. The hi stologic differences found in the RGEA may indicate an increased prope nsity for atherosclerosis of the RGEA as compared with the IMA. Some c oncern regarding the long-term patency of the RGEA in myocardial revas cularization is warranted.