SHORT-TERM RESULTS OF BOVINE INTERNAL MAMMARY ARTERY USE IN CARDIOVASCULAR-SURGERY

Over a 14-month period, 28 bovine internal mammary arteries (Bioflow, Bio-Vascular, Inc.; St. Paul, Minnesota, USA) were implanted in 20 pat ients at our institutions. In 8 patients, the bovine internal mammary artery was used to bypass coronary vessels: in 4 of these patients, co ronary artery bypass grafting was performed because of coronary diseas e (1 type-I aortic dissection); in the other 4 (all with aortic dissec tion), the modified Bentall technique was used for coronary artery rei mplantation. In the remaining 12 patients, the bovine artery was used in vascular surgery: as a graft for lower-extremity occlusive disease (4 patients), arteriovenous fistula (2 patients), and aorticorenal byp ass (I patient); and as a patch to the carotid bifurcation or the comm on femoral artery in association with endarterectomy (5 patients). The 21 bovine grafts were all 5 mm in diameter; the 7 bovine patches were 4 mm. Of the 8 coronary bypass patients, 2 who underwent coronary art ery bypass grafting had acute postoperative myocardial infarctions, an d 2 who underwent the modified Bentall technique died in surgery. Foll ow-up angiography showed complete bovine internal mammary artery graft occlusion in 2 patients; 2 symptom-free patients refused examination. Of the vascular surgery patients, 1 with mild left leg claudication h ad graft occlusion, shown by angiography, 4 months after surgery. Rena l scintigraphy performed in the patient with aorticorenal bypass 4 mon ths after operation showed no blood flow to the kidney. Two patients d ied for reasons unrelated to bovine mammary artery grafting. The remai ning patients are well and free of complications. In view of the high incidence of early occlusion, we do not recommend use of the bovine in ternal mammary artery graft in coronary surgery In vascular surgery, t he results are more encouraging; however studies comprising a larger n umber of patients and longer follow-up are needed to determine whether the use of the bovine internal mammary artery graft can be recommende d.