Study on the effect of location of intracranial arterial stenosis on the safety of stenting

Objective To investigate the effect of location of intracranial arterial stenosis on the safety of intracranial stenting. Methods A total of 73 patients with symptomatic intracranial atherosclerotic stenosis (ICAS) were divided into intracranial internal carotid artery (IICA, N = 18), middle cerebral artery (MCA)-M1 segment (MCA-M1, N = 11), intracranial vertebral artery (IVA, N = 27) and basilar artery (BA, N = 17). All of them underwent intracranial stenting. The improvement of intracranial arterial stenosis, cerebrovascular complications including perforating events, artery dissection, in-stent thrombosis, distal stent arterial embolism and cerebral hyperperfusion, and neurological complications including transient ischemic attack (TIA), ischemic stroke and intracranial hemorrhage were recorded. Modified Rankin Scale (mRS) was used to evaluate the prognosis 30 d after operation.  Results A total of 73 stents were implanted in 73 patients (35 Apollo balloon-expandable stents and 38 Wingspan self-expandable stents). Among them, 10 cases (10/18) were treated with Apollo stents and 8 cases (8/18) with Wingspan stents in IICA group, 5 cases (5/11) were treated with Apollo stents and 6 cases (6/11) with Wingspan stents in MCA-M1 group, 16 cases (59.26%, 16/27) were treated with Apollo stents and 11 cases (40.74%, 11/27) with Wingspan stents in IVA group, and 4 cases (4/17) were treated with Apollo stents and 13 cases (13/17) with Wingspan stents in BA group. No significant difference was seen in stent type among 4 groups (χ 2 = 7.422, P = 0.201). The stenosis rate of IICA group after treatment [(10.94 ± 1.99)%] was significantly improved than before treatment [(90.89 ± 7.71)%; t = 69.545,  P = 0.000]. The stenosis rate of MCA-M1 group after treatment [(10.37 ± 2.14)%] was significantly improved than before treatment [(87.64 ± 9.46)%;  t = 26.000,  P = 0.000]. The stenosis rate of IVA group after treatment [(11.02 ± 1.99)% ] was significantly improved than before treatment [(89.11 ± 7.97)%;  t = 50.726,  P = 0.000]. The stenosis rate of BA group after treatment [(10.99 ± 3.39)%] was significantly improved than before treatment [(91.35 ± 5.62)%;  t = 69.545,  P = 0.000]. In 73 patients, cerebrovascular complications occurred in 11 cases (15.07%), including 4 cases of perforating events, 4 cases of artery dissection, one case of in-stent thrombosis and 2 cases of distal stent arterial embolism. There were 3 cases (3/18) in IICA group, including 2 cases of artery dissection and one case of distal stent arterial embolism, and 8 cases (8/17) in BA group, including 4 cases of perforating events, 2 cases of artery dissection, one case of in-stent thrombosis and one case of distal stent arterial embolism. No cerebrovascular complications occurred in MCA-M1 group and IVA group. The difference among 4 groups was statistically significant ( H = 63.134,  P = 0.000). Neurological complications occurred in 6 cases (8.22%), including 4 cases of TIA and 2 cases of ischemic stroke. There was one case (1/18) of ischemic stroke in IICA group, and 5 cases (5/17) in BA group, including 4 cases of TIA and one case of ischemic stroke. No neurological complications occurred in MCA-M1 group and IVA group. The difference among 4 groups was statistically significant ( H = 65.698, P = 0.003). At 30 d after operation, there was one case with mRS 1 score in IICA group and one in BA group. The total rate of good prognosis 30 d after operation was 97.26% (71/73).  Conclusions The location of intracranial arterial stenosis have a great influence on the risk of perioperative cerebrovascular and neurological complications in the intracranial stenting, and the overall prognosis is good. DOI: 10.3969/j.issn.1672-6731.2017.11.006