IS CAROTID ENDARTERECTOMY JUSTIFIED IN PATIENTS WITH SEVERE CHRONIC RENAL-INSUFFICIENCY

We evaluated the effect of chronic renal insufficiency (CRI) and commo nly associated co-morbid conditions on the risk of adverse events (str oke, cardiac events, and death) within 30 days after carotid endartere ctomy (CEA). Renal function of patients undergoing CEA from 1980 to 19 94 was categorized as normal (creatinine<1.5 mg/dl), mild CRI (creatin ine 1.5-2.9 mg/dl), or severe CRI (creatinine>2.9 mg/dl). Renal functi on, age, gender, indications for surgery, cardiac disease, chronic pre operative hypertension, diabetes mellitus, smoking history, severe per ioperative hypertension or hypotension, intraoperative shunting, and p atch closure of the carotid artery were evaluated for their influence on the incidence oi adverse events within 30 days after surgery. The t iming of postoperative stroke and mechanism of stroke was determined w hen possible. A total of 237 patients underwent 285 CEAs. No significa nt differences were found in demographic or clinical characteristics b etween patients with normal or abnormal renal function. Postoperative stroke and death occurred following three (43%) of seven CEAs in six p atients with severe CRI, significantly greater than the 6% incidence o f stroke and 1% mortality following 264 CEAs in 221 patients with norm al renal function (p<0.001 and p<0.001, respectively). Of three patien ts with severe CPI suffering postoperative stroke, two had severe, dif ficult to control perioperative hypertension. Two patients with severe CRI who survived 30 days after operation suffered strokes 3 and 4 mon ths postoperatively with one stroke-related death and another death no t directly related to the stroke. One patient with severe CRI who surv ived CEA without stroke was alive 6 months after surgery. The 0% incid ence of stroke and death following 14 CEAs in 10 patients with mild CR I was not significantly different from that in patients with normal re nal function. Postoperative stroke was not associated with age, gender , history of cardiac disease, chronic preoperative hypertension, diabe tes, smoking, or use of intraoperative shunts or patch closure. All th ree cardiac events occurred in diabetic patients, although they consti tuted only 26% of operations (p=0.003). Other clinical characteristics were not associated with the occurrence of cardiac events. Patients w ith severe CRI are at significantly greater risk than others for posto perative stroke and death following CEA, possibly related to difficult y controlling severe perioperative hypertension. Age, gender, smoking, preoperative hypertension, diabetes, and known cardiac disease are no t associated with an increased risk of postoperative stroke in any pat ient group. CEA can be justified only for carefully selected patients with severe CPI who have symptomatic carotid disease, acceptable opera tive risk factors, and a good long-term life expectancy. CEA in patien ts with mild CRI is associated with low risk, and these patients may b e treated with the same consideration as patients with normal renal fu nction.