Carotid Endarterectomy Based on Duplex Ultrasound in Patients with and without Hemispheric Symptoms

Abstract

Carotid endarterectomy is the most commonly performed vascular procedure. This retrospective study was conducted to determine the efficacy of duplex imaging as the sole diagnostic study for preoperative evaluation of symptomatic and asymptomatic patients who underwent carotid endarterectomy. We conducted a retrospective case series analysis in a community teaching hospital. From January 1994 to September 1998, 316 patients underwent carotid endarterectomy for carotid stenosis. A total of 177 patients were symptomatic and 139 patients were asymptomatic. Angiography was performed routinely in the beginning of the study but later was performed only in selected patients. Preoperative duplex ultrasound of carotid artery was performed by a laboratory accredited by the Intersocietal Commission for the Accreditation of Vascular Laboratories. Data were reviewed to obtain morbidity and mortality rates, and duplex imaging results were compared with operative findings. Cost and risk analysis of carotid angiography reviewed. This study reviewed variables of age, sex, race, diabetes, smoking, hypertension, hypercholesterolemia, coronary artery disease, and renal failure. Five patients had a lesion in the proximal portion of the carotid artery by duplex imaging criteria. Duplex ultrasound results were grossly confirmed intraoperatively in all patients except in one patient who was found to have complete occlusion of carotid artery whose duplex was read as high-grade stenosis. The duration of stay ranged from two to 30 days. This duration was influenced by patients’ comorbid conditions, postoperative complications or simultaneous coronary artery bypass graft. Four patients had a stroke within 30 days of surgery making the stroke rate of 1.26 per cent. There has been considerable debate on the use of duplex ultrasound as the only method of preoperative evaluation of carotid stenosis before carotid endarterectomy. Our study demonstrates that it is safe to perform carotid endarterectomy based on neurologic history and duplex ultrasound with good technical quality performed in an accredited vascular laboratory. This approach eliminates the cost and risk associated with angiography. Proximal carotid and intrathoracic lesions are rare and can be predicted by the duplex study. We think that carotid angiography is required only when duplex imaging is suboptimal or equivocal in the presence of atypical symptoms or uncommon vascular abnormalities.