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 patients at our institutions. In 8 patients, the bovine internal mammary artery was used to bypass coronary vessels: in 4 of these patients, coronary artery bypass grafting was performed because of coronary disease (1 type-I aortic dissection); in the other 4 (all with aortic dissection), the modified Bentall technique was used for coronary artery reimplantation. 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 bypass (1 patient); and as a patch to the carotid bifurcation or the common 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 artery bypass grafting had acute postoperative myocardial infarctions, and 2 who underwent the modified Bentall technique died in surgery. Follow-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 had graft occlusion, shown by angiography, 4 months after surgery. Renal scintigraphy performed in the patient with aorticorenal bypass 4 months after operation showed no blood flow to the kidney. Two patients died for reasons unrelated to bovine mammary artery grafting. The remaining patients are well and free of complications. In view of the high incidence of early occlusion, we do not recommend use of the bovine internal mammary artery graft in coronary surgery. In vascular surgery, the results are more encouraging; however, studies comprising a larger number of patients and longer follow-up are needed to determine whether the use of the bovine internal mammary artery graft can be recommended.