Pipeline for uncoilable or failed aneurysms: 3-year follow-up results

Abstract

OBJECTIVE The long-term effectiveness of endovascular treatment of large and giant wide-neck aneurysms using traditional endovascular techniques has been disappointing, with high recanalization and re-treatment rates. Flow diversion with the Pipeline Embolization Device (PED) has been recently used as a stand-alone therapy for complex aneurysms, showing significant improvement in effectiveness while demonstrating a similar safety profile to stent-supported coil treatment. However, relatively little is known about its long-term safety and effectiveness. Here the authors report on the 3-year safety and effectiveness of flow diversion with the PED in a prospective cohort of patients with large and giant internal carotid artery aneurysms enrolled in the Pipeline for Uncoilable or Failed Aneurysms (PUFS) trial. METHODS The PUFS trial is a prospective study of 107 patients with 109 aneurysms treated with the PED. Primary effectiveness and safety end points were demonstrated based on independently monitored 180-day clinical and angiographic data. Patients were enrolled in a long-term follow-up protocol including 1-, 3-, and 5-year clinical and imaging follow-up. In this paper, the authors report the midstudy (3-year) effectiveness and safety data. RESULTS At 3 years posttreatment, 74 subjects with 76 aneurysms underwent catheter angiography as required per protocol. Overall, complete angiographic aneurysm occlusion was observed in 71 of these 76 aneurysms (93.4% cure rate). Five aneurysms were re-treated, using either coils or additional PEDs, for failure to occlude, and 3 of these 5 were cured by the 3-year follow-up. Angiographic cure with one or two treatments of Pipeline embolization alone was therefore achieved in 92.1%. No recanalization of a previously completely occluded aneurysm was noted on the 3-year angiograms. There were 3 (2.6%) delayed device- or aneurysm-related serious adverse events, none of which led to permanent neurological sequelae. No major or minor late-onset hemorrhagic or ischemic cerebrovascular events or neurological deaths were observed in the 6-month through 3-year posttreatment period. Among 103 surviving patients, 85 underwent functional outcome assessment in which modified Rankin Scale scores of 0-1 were demonstrated in 80 subjects. CONCLUSIONS Pipeline embolization is safe and effective in the treatment of complex large and giant aneurysms of the intracranial internal carotid artery. Unlike more traditional endovascular treatments, flow diversion results in progressive vascular remodeling that leads to complete aneurysm obliteration over longer-term follow-up without delayed aneurysm recanalization and/or growth. Clinical trial registration no.: NCT00777088 (clinicaltrials.gov).

European Multicenter Study for the Evaluation of a Dual-Layer Flow-Diverting Stent for Treatment of Wide-Neck Intracranial Aneurysms: The European Flow-Redirection Intraluminal Device Study

“…In the Pipeline for Uncoilable or Failed Aneurysms (PUFS) trial, the rate of completely occluded aneurysms at 1 year was 86.8% 1 and climbed to 93.4% at 3 years and 95.2% at 5 years. 16,17 Aneurysms in PUFS, however, were notably larger at a median aneurysm diameter of 17.5 mm compared with 7.6 mm in the EuFRED. Aneurysms of Ͼ20 mm were also associated with a lower rate of occlusion in the EuFRED.…”

Pipeline embolization device for recurrence of previously treated aneurysms

“…When evaluating the 3-year follow-up results for the Pipeline for Uncoilable or Failed Aneurysms (PUFS) trial, the investigators found that 15 patients had a residual aneurysm or residual neck. Four of these patients underwent further treatment with a second PED (Table 3), 3 and 2 (50%) of these 4 progressed to complete occlusion. The 2 patients treated with PEDs at our institution following failed flow diversion each presented with large fusiform aneurysms of the ICA, requiring multiple stents during their first and second treatments.…”

“…Given that the PED is still in its infancy, little literature exists regarding PED failures and treatment options for recurrent aneurysms following prior PED apart from a few case reports. 3,7,15 In a study evaluating the treatment of 119 unruptured aneurysms with a PED, 7 patients experienced occlusion failure, and in 3 of the 7 cases, this residual was treated with a second PED. 7 Unfortunately, adequate follow-up to assess the durability of this second treatment was not available.…”

Contemporary endovascular and open aneurysm treatment in the era of flow diversion

“…Conversely, the PUFs trial demonstrated that flow diversion for giant ICA aneurysms is a safer alternative (93% occlusion rate, 5% mortality rate), with many aneurysms that were incompletely occluded initially becoming completely occluded over time 5 6. Endoluminal reconstruction of the diseased segment leads to aneurysm occlusion and anatomical resolution of the mass effect over time with low rates of complications (6% of major stroke or death) 6. The procedure is performed relatively quickly, and most patients are discharged home the following day.…”

“…In contrast to the high occlusion rate when flow diversion is performed as an initial treatment (93%),6 flow diversion for recurrent aneurysms is less effective 40. Daou et al found that if a stent is already present, flow diversion for a recurrent aneurysm had an occlusion rate of 56%, with 10% of cases requiring retreatment 40.…”