Useage of stent grafts in the treatment of extracranial carotid artery stenosis

Useage of Stent Grafts in the Treatment of Extracranial Carotid Artery Stenosis Purpose: To evaluate the effectiveness of coating the atherosclerotic plaque by a covered stent before the implantation of bare carotid stent to prevent the distal microembolic complications of extracranial carotid artery stenting (CAS). Material and Methods: Fifty patients who had CAS indication aged 52 to 82 were included in the study. Fourteen patients were treated by using both covered and bare stents in the same lesion and 36 patients were treated only by bare carotid stents. Patients who had tandem lesions in the other segments of carotid artery were not included in the study. Covered stent was implanted to the most stenotic segment of internal carotid artery without covering the orifice of external carotid artery. Distal protection devices were used in all procedures. Antiaggregation and anticoagulation therapies were applied to all patients and drug sensitivity was tested. Predilatation was applied in 20 lesions. Postdilatation was applied in all. Acute ischemic foci due to possible microembolic complications were evaluated by DWI MRI examinations just before the process and one day after the process. Stent patency was checked by DSA at the end of the sixth month and by Doppler ultrasonography on first day, first, third and sixth months. Results: Acute ischemic lesions were detected in seven of 14 (50%) patients in the covered stent group and in 30 of 36 patients (83.3%) in the control group. Significant restenosis (over 50%) was detected in two patients of each group (13.3% in the covered stent group and 5.6% in the control group). Morbidity and mortality rates were, respectively, 14.3% and 0% in the covered stent group and 19.4% and 0% in the control group. Conclusion: Covered stents are effective to decrease the microembolic complications of CAS. Nevertheless high restenosis ratio restricts the usage in accordance with the literature. Key Words: Carotid artery stenosis, Carotid artery stenting, Stent-graft