Can duplex ultrasonography select appropriate patients for carotid endarterectomy?

Objectives: This study investigated the reliability of carotid duplex ultrasound (DUS) to identify appropriate candidates for capotid endarterectomy (CEA) according to a panel of vascular specialists. Design: Prospective study. Material: 102 patients with 145 carotid bifurcation stenosis or occlusions. Methods: All patients who required a carotid angiogram were evaluated using DUS followed by carotid angiography. A blinded panel of four vascular specialists individually decided whether CEA would be appropriate for each patient based on pre-angiographic information. Angiograms were then shown to panelists to see if their management decision was altered by the angiogram. Results: For stenosis greater than or equal to 80% on DUS (n = 60), panelists unanimously agreed on CEA without angiography in 57 lesions. In 50 lesions (87.7%), angiography showed greater than or equal to 70% stenosis and the management plan remained unchanged. For the other seven lesions, intracranial aneurysms (n=2), tandem intracranial lesion (n=1), unsuspected proximal common carotid lesion (n=1), a 40% stenotic lesion (n=1), and high carotid bifurcations (n=2) were seen. In lesions with 50-79% stenosis on DUS (n=66), none of the panelists recommended CEA without prior angiography. Eighteen (27%) of these lesions were greater than or equal to 70% stenosed on angiogram. Complications of angiograms included one stroke, one haematoma, and one severe allergic reaction. Conclusion: Carotid duplex ultrasonography without angiography can reliably select lesions appropriate for surgery only when critical stenosis greater than or equal to 80% is chosen. Routine angiography is recommended for carotid stenosis of 50-79% when CEA is considered.