PREDICTING COMPLICATIONS OF CAROTID ENDARTERECTOMY

Background and Purpose: Carotid endarterectomy has been shown to be be neficial in patients with high-grade carotid stenosis and ipsilateral transient ischemic attack or stroke. This benefit will be realized onl y if the operation is performed safely. We sought to determine the ext ent to which clinically significant adverse events occurring after car otid endarterectomy can be predicted from clinical data available befo re surgery. Methods: Eleven hundred sixty patients were randomly selec ted from all patients who underwent carotid endarterectomy and were di scharged during the calendar years 1988, 1989, and 1990 in 12 academic medical centers in 10 states. Clinical data abstracted from hospital charts were analyzed retrospectively. A model was developed and valida ted to predict the occurrence of stroke, myocardial infarction, or dea th during the postoperative period of hospitalization. Results: Eighty patients (6.9%) suffered at least one adverse event. Rates for indivi dual complications were as follows: death, 1.4%; nonfatal stroke, 3.4% ; nonfatal myocardial infarction, 2.1%; and nonfatal stroke or death, 4.8%. Significant predictors of adverse events were age 75 years or ol der, symptom status (ipsilateral symptoms versus asymptomatic or nonip silateral symptoms), severe hypertension (preoperative diastolic blood pressure of greater than 110 mm Hg), carotid endarterectomy performed in preparation for coronary artery bypass surgery, history of angina, evidence of internal carotid artery thrombus, and internal carotid ar tery stenosis near the carotid siphon. The presence of two or more of these risk factors was associated with a nearly twofold increase in ri sk of an adverse event (relative risk, 1.7; 95% confidence interval, 1 .0 to 3.0). Conclusions: Clinical data can be used to stratify patient s undergoing carotid endarterectomy according to risk of postoperative in-hospital stroke, myocardial infarction, or death.