Purpose To examine clinical and angiographic outcomes in a cohort of consecutive patients with ruptured intracranial aneurysms treated with the Pipeline Embolization Device (PED) at a referral center.

Methods We conducted a retrospective review of all patients with ruptured intracranial aneurysms treated with the PED in our center between January 20^th, 2012 and March 9^th, 2017. Baseline patient and aneurysm characteristics as well as complications were recorded. Aneurysm volumes in initial and follow-­up angiographic studies were calculated using AngioCalc. Clinical outcomes were categorized using the modified Rankin Scale (mRS).

Results 16 patients underwent 17 PED procedures to treat 18 ruptured intracranial aneurysms during the study period. 11 patients were women (69%) and 5 men (31%). Mean age was 53 years (range 13-­92 years). Hemorrhage distribution was diffuse in 12 patients (75%), perimesencephalic in 2 patients (13%), peripheral in 1 patient (6%) and intraventricular in 1 patient (6%). Mean admission Hunt-Hess scale was 2.4 (median 2, range 1-5). 5 patients required external ventricular drain (EVD) placement (31%). 13 patients were premedicated with aspirin/clopidogrel with VerifyNow testing (81%), 1 with warfarin/clopidogrel with VerifyNow testing (6%) and 2 with aspirin/ticagrelor without VerifyNow testing (13%). 11 aneurysms were treated acutely (61%, mean 3.1 days after hemorrhage, range 0-7 days), and 7 subacutely (39%, mean 31 days after hemorrhage, range 8–76 days). 9 aneurysms were blister (50%), 5 saccular (28%), 3 dissecting (17%) and 1 fusiform (6%). 11 aneurysms were located in the internal carotid artery (61%), 3 in the basilar artery (17%), 2 in the middle cerebral artery (11%) and 2 in the anterior cerebral artery (11%). Mean aneurysm size was 3.3mm (1.5–10.8mm), mean neck was 2.8mm (0.6-8.3mm), mean dome-­to-­neck ratio was 1.1 (0.7–2.8). Mean number of PEDs deployed per aneurysm was 1.1. Adjunctive coiling was performed in 3 aneurysms (17%, mean 2.3 coils deployed). There were 1 intra-operative (6%) and 2 peri-operative (12%) complications, none led to a disabling neurological deficit (mRS≥3). There were 2 post-­operative aneurysm re-ruptures (11%), 1 occurring on post-operative day 1 without clinical sequelae, and 1 occurring on post-operative day 14 upon EVD removal and resulting in the patient’s death. Both aneurysms with post-operative re-rupture were dissecting anterior cerebral artery aneurysms treated acutely without adjunctive coiling. Treatment-related mortality was 6.3%, and overall mortality was 12.5%. Angiographic follow-­up was available in 8 aneurysms (44%, 6 follow-ups currently pending), with a mean time to last angiographic follow-­up of 12.4 months. At last follow­-up, 7 aneurysms were completely occluded (88%) and 1 aneurysm had near-complete occlusion (12%, 92.9% volume reduction). The nearly-completely-occluded aneurysm was re-treated with placement of an additional PED. At last clinical follow-up, 11 patients had mRS 0–2 (68.8%), 3 had mRS 3 (18.8%) and 2 had expired (12.5%).

Conclusion The PED is a safe and effective treatment for ruptured intracranial aneurysms, with high medium-term complete aneurysm occlusion rates, low re-­treatment rates, and a low rate of major treatment-related complications. The risk of post-operative aneurysm re-rupture may be minimized by adjunctive use of coils and subacute PED embolization whenever possible.

Disclosures: J. Delgado Almandoz: 2; C; Medtronic Neurovascular, Accriva Diagnostics. Y. Kayan: 2; C; Medtronic Neurovascular. K. Uittenbogaard: None. J. Scholz: None. A. Milner: None. J. Fease: None. A. Wallace: None. K. Nelson: None. M. Mulder: None.