Risk factors in a community experience with carotid endarterectomy.

Experience with 1035 carotid endarterectomies in a single community over a 2-year period was analyzed. Twenty-two surgeons working in six hospitals were involved. All surgeons had full-time or part-time appointments at the University of Rochester, 18 had special interest in vascular surgery, and eight had obtained a certificate of qualification in vascular surgery. Mortality rate was 1.4% (14 deaths), with additional permanent, nonfatal, neurologic morbidity of 3.4%. Mortality and morbidity were independent of surgeon, caseload, or hospital. Age and prior history of myocardial infarction influenced the incidence of postoperative myocardial infarction but not the incidence of death or neurologic morbidity. Factors that increased the risk of postoperative death or neurologic complication included hypertension; contralateral carotid disease as manifested by stroke, endarterectomy, or occlusion; whether the patient was a woman; and symptoms of crescendo ischemia. Lack of preoperative neurologic symptoms was correlated with decreased risk of myocardial infarction and neurologic complications. Overall mortality and neurologic morbidity associated with operation for "asymptomatic stenosis" was 3.1% (seven of 222 cases). However, the incidence of contralateral carotid disease was high in the patients in the asymptomatic group (60%), and all complications in this group occurred in patients with prior contralateral carotid endarterectomy or occlusion (p less than 0.05).