Renal endarterectomy vs. bypass for combined aortic and renal reconstruction: Is there a difference in clinical outcome?

Are there differences in the patient characteristics and clinical outcome for transaortic renal endarterectomy vs. bypass grafting when either technique is combined with infrarenal aortic replacement for occlusive or aneurysmal disease? Two common perceptions persist: (1) combined aortic and renal procedures have a high risk and (2) bypass is easier and safer than endarterectomy. To address these controversies we compared 52 consecutive patients undergoing concomitant aortic and renal reconstruction between 1987 and 1991: 26 with bypass and 26 with endarterectomy. Bypass patients were older (70 vs. 64 years, p=0.001), had more extensive plaque extending into the distal renal artery and more severe baseline azotemia (creatinine=2.6 vs 1.7 mg/dl, p=0.01), more clinically evident coronary heart disease (89% vs. 56%, p=0.001), and a greater need for nephrectomy of a small nonfunctional pressor kidney (23% vs. 0%) than endarterectomy patients. In contrast, endarterectomy patients more commonly required aortic replacement for occlusive disease than for an aortic aneurysm (endarterectomy: 65% vs. 35%; bypass: 19% vs 81%, p=0.002)and tended to require more intraoperative technical revisions (12% vs. 4%) than bypass patients. Both groups, however, experienced no operative mortality, had similar cardiorespiratory morbidity, and achieved equal improvement in hypertension (69% vs. 65%). Bypass patients, who already had more severe preoperative azotemia than endarterectomy patients, showed less improvement in the creatinine level (Cr=2.1 vs. 1.4 mg/dl, p=0.01)and had greater need for late dialysis (30% vs. 4%, p=0.01). Only one patient on dialysis had graft occlusion. We conclude that patients requiring bypass are generally at a more advanced stage of both cardiovascular and renal disease and have a greater need for late dialysis than was previously recognized. Transaortic endarterectomy is a safe and effective choice in patients with bilateral orificial renal atheroma and aortic occlusive disease. Both procedures currently carry a lower operative risk than was previously predicted and have equal effectiveness in controlling renovascular hypertension.