Treatment of large and giant posterior communicating artery aneurysms with the Surpass streamline flow diverter: results from the SCENT trial

Abstract

BackgroundThe Surpass flow diverter was developed to treat intracranial aneurysms not amenable to standard treatment. Indications for use allow placement in the internal carotid artery to the terminus, including the communicating artery segment.MethodsThe Surpass Intracranial Aneurysm Embolization System Pivotal Trial to Treat Large or Giant Wide Neck Aneurysms (SCENT) trial is an international, multicenter, prospective, non-randomized trial comparing the outcomes of Surpass flow diverter treatment with historic control designed to evaluate the effectiveness and safety of Surpass for the treatment of wide neck (≥4 mm) large or giant intracranial aneurysms ≥10 mm. The primary effectiveness endpoint is the percentage of subjects with 100% aneurysm occlusion without significant stenosis of the parent artery and without retreatment of the target aneurysm at 12 months. The primary safety endpoint is the percentage of subjects experiencing neurologic death or major ipsilateral stroke at 12 months. We report the effectiveness and safety of flow diversion in the subgroup of posterior communicating artery (PComA) aneurysms.ResultsOf the 180 patients treated, 38 harbored a PComA aneurysm. Mean aneurysm size was 12.2 mm and mean neck width was 4.8 mm. The mean number of Surpass devices used was 1.1 per procedure, with 94.7% of aneurysms treated with one flow diverter. The 12 month primary effectiveness rate was 73.7% (28/38). At 36 months, 68.4% (26/38) of aneurysms remained completely occluded. The 12 month major ipsilateral stroke or neurological death rate was 10.5%. No patients with PComA occlusion after flow diverter placement (54.5%) had clinical sequelae.ConclusionsSCENT demonstrated acceptable 12 month effectiveness of flow diversion in PComA aneurysms. Despite associated PComA occlusions in many cases, arterial occlusions were clinically silent.Trial registration numberURL: https://www.clinicaltrials.gov. Unique identifier: NCT01716117.

Flow Diverter Performance in Aneurysms Arising From the Posterior Communicating Artery: A Systematic Review and Meta-Analysis

“…Two patients died from the complications, one case presented a hemorrhage during retreatment of the target aneurysm, and the other had a fatal vessel perforation. 3,19 Details of the complications are provided in Supplemental Table 8 , http://links.lww.com/NEU/D806. Finally, the rate of PComA patency at final follow-up was 76% (CI 57%-89%, I 2 = 81%) (Figure 1C).…”

“…21 That is of interest considering that jailing of the PComA carries a theoretical concern for vessel size reduction or occlusion which can lead to infarction in critical territories supplied by the lateral thalamic perforators such as the anterolateral thalamic nuclei, internal capsule, and optic tract. 3 Several studies have evaluated PComA patency after flow diversion, reporting occlusion rates ranging from 22% to 77%. We specifically found that the PComA patency rate was 76%.…”

“…2,6,10,19,20 Only one study had a prospective multicenter design. 3 The number of participants per study ranged from 5 to 57.…”

“…This could be explained by the following reasons: (1) the events being clinically silent (which seems unlikely because of the eloquence of the territories supplied), (2) the development of collateral flow from near vascular territories, or (3) the potential change in the direction of flow from the same territories. 3,19 Finally, we noted that because of the lack of disaggregated data, we could not evaluate the patency considering only the patients with FPCo-mAs. Overall, our findings show that the placement of the FD across the lumen of the PComA is safe with a low risk of ischemic/ hemorrhagic events.…”

“…Particularly, flow diversion has shown satisfactory rates of aneurysm occlusion and a low incidence of safety events in the treatment of PComA aneurysms. [2][3][4][5] Nevertheless, the use of FDs in the setting of a fetal PComA (FPComA) or a hypoplastic P1 segment of the posterior cerebral artery is controversial. Previously published series have postulated concerns after the implantation of FDs in these cases because of the decreased efficacy and high recurrence rates caused by the high flow through the FPComA, which prevents endothelialization, and the potential risk for ischemic complications (large infarcts) if complete arterial occlusion occurs.…”