The endarterectomy-produced common carotid artery step: A harbinger of early emboli and late restenosis

Purpose: This study analyzes the role of the carotid endarterectomy (CEA)-produced common carotid step or shelf on early and late CEA outcome. A simple method of reconstruction that covers the exposed media and intima of the step and smooths out the flow channel is presented. Methods: Since 1984 intraoperative geometric measurements were made on 1019 CEA. Duplex scans were made after surgery on 968 (95%); 234 (23%) were monitored for at least 5 years. Of the first 920 CEA, 261 (28%) had a step greater than or equal to 2 mm. Of the last 99 operations, the 27 (27%) with a step greater than or equal to 2 mm had inversion plication reconstruction of the step, Results: Three patients had early post-CEA neurologic events attributed to a common carotid step, two had transient-ischemic attacks, and one had a mild stroke. All three had a CEA-produced step greater than or equal to 2 mm (1.2% of 261, p = 0.03 when compared with no unexplained early neurologic events in the 659 without a step). Duplex scans were normal in all three except for a common carotid artery step. Six patients had seven reoperations for common carotid artery restenosis at 23 to 104 months (mean 73 months) after CEA. All had a step greater than or equal to 2 mm at the origin CEA (2.7% of 261, p = 0.001 when compared with no reoperations for common carotid artery stenosis in the 659 CEA without a step). All but one patient had >75% restenosis. Four were asymptomatic. All seven with restenosis were within 2 mm of the original common carotid end point step. Four restenoses were concentric, two eccentric, and one ulcerated. Six of the seven arteries were originally reconstructed with a greater saphenous vein patch that extended 3 to 6 mm proximal to the step. Early postoperative duplex scans of the 27 recent CEA with step reconstruction demonstrated a tortuous hut-smooth common carotid artery flow channel. Conclusion: The CEA-produced common carotid artery step is a potential source of both early postoperative emboli and late restenosis. The incidence is approximately 4% in patients with a CEA step greater than or equal to 2 mm. C-EA vein patch reconstruction does not prevent restenosis in the region of the step but may lower the incidence. Although not proven, reconstruction techniques directed at covering the exposed step media and intima and smoothing the flow channel may favorably alter outcome.