The clinical data and findings on the early postoperative intravenous digital subtraction angiograms (IVDSA's) were studied in 61 patients undergoing 70 consecutive conventional carotid endarterectomies and in 46 patients undergoing 50 consecutive carotid endarterectomies with a saphenous vein patch graft (SVPG). The IVDSA's were considered normal in 50 of 70 conventional carotid endarterectomies and in 46 of 50 carotid endarterectomies with SVPG (p = 0.004). The internal carotid artery (ICA) origin was consistently larger and had a more normal configuration after carotid endarterectomy with SVPG. Ballooning at the endarterectomy site was an uncommon finding and occurred with similar frequency in both groups; that is, after three conventional carotid endarterectomies and two carotid endarterectomies with SVPG. In the conventional group, early symptomatic thrombosis occurred in the ICA in one patient and in the common carotid artery (CCA), ICA, and external carotid artery (ECA) in two patients. Silent ICA occlusion was seen in three patients in the conventional group. There were no occlusions in the SVPG group (p = 0.04). Stenosis at the distal end of the ICA arteriotomy was found after nine conventional carotid endarterectomies, and was mild (less than or equal to 33% reduction in the lumen) in seven patients, moderate (34% to 66%) in one, and severe (greater than or equal to 67%) in one. Mild distal ICA stenosis was seen in one case after carotid endarterectomy with a SVPG (p = 0.03). Stenosis of 33% or less was found at the proximal end of the CCA arteriotomy after two carotid endarterectomies in the conventional group and one carotid endarterectomy in the SVPG group. Four patients in the conventional group suffered a postoperative cerebral infarct and one patient in the SVPG group suffered a postoperative brain-stem infarct (p = 0.28). The authors' findings have led them to routinely use a SVPG in carotid endarterectomy.