Efficacy and Safety of Flow-Diverter Therapy for Recurrent Aneurysms after Stent-Assisted Coiling

Neqstent coil-assisted flow diverter (NQS) for the treatment of bifurcation aneurysms: the coil-assisted flow diversion safety and performance study (CAFI)

BackgroundThe Neqstent coil-assisted flow diverter (NQS) is a neck bridging device to facilitate coil occlusion of intracranial aneurysms. CAFI is a prospective, single-arm, multicenter study on the safety and performance of the NQS adjunctive therapy device together with platinum coils for treatment of unruptured intracranial aneurysms.

METHODS

Thirty-eight patients were enrolled. Primary endpoints were occlusion at 6 months for efficacy, and any major stroke or non-accidental death up to 30 days or major disabling stroke within 6 months for safety. Secondary endpoints were re-treatment rate, procedure time, and procedure/device-related adverse events. Procedural and follow-up imaging was reviewed by an independent core laboratory. Adverse events were reviewed and adjudicated by a clinical events committee.

RESULTS

The NQS was successfully implanted in 36/38 aneurysms, 2/38 in the intention-to-treat group did not receive a NQS and were excluded from follow-up after 30 days. In the per protocol group (PP), 33/36 patients were available for angiographic follow-up. Device related adverse events were recorded in 4/38 (10.5%) patients, one hemorrhagic and three thromboembolic. In the PP group, immediate post-treatment adequate occlusion (RR1 and RR2) was seen in 9/36 (25%) and progressed to 28/36 (77.8%) at 6 months. Complete occlusion (RR1) was achieved in 29/36 (80.6%) at the last available angiogram (3/36 were post procedure). The mean procedure time was 129 min (50-300 min, median 120 min).

CONCLUSION

The NQS in conjunction with coils appears to be effective in the treatment of intracranial wide-neck bifurcation aneurysms, but its safety remains to be proved in larger series.

TRIAL REGISTRATION NUMBER

NCT04187573.

Sequential Flow Diversion After Nitinol Stent Placement for a Large, Matricidal Cavernous Internal Carotid Artery Aneurysm: Technical Video

The Surpass Evolve flow diverter is a novel 64-wire braided intravascular stent approved to treat unruptured large or giant saccular wide-neck or fusiform intracranial aneurysms of the intracranial internal carotid artery.1-3 Flow diverting stents have been used for the treatment of previously stented aneurysms, including residual aneurysms following prior flow diversion.5-8 This patient initially presented with a large symptomatic matricidal cavernous ICA aneurysm4 that was treated with stand-alone Neuroform Atlas stenting at an outside hospital. Here we present a video demonstrating the placement of sequential Surpass Evolve flow diverter stents within a Neuroform Atlas nitinol stent.

Woven endo bridge device for recurrent intracranial aneurysms: A systematic review and meta-analysis

BACKGROUND

Recurrent intracranial aneurysms present a significant clinical challenge, demanding innovative and effective treatment approaches. The Woven EndoBridge (WEB) device has emerged as a promising endovascular solution for managing these intricate cases. This study aims to assess the safety and efficacy of the WEB device in treating recurrent intracranial aneurysms.

METHODS

We conducted a comprehensive search across multiple databases, including PubMed, Scopus, Embase, and Web of Science, from inception to June 5, 2023. Eligible studies focused on evaluating WEB device performance and included a minimum of five patients with recurrent intracranial aneurysms. The complete and adequate occlusion rates, neck remnant rates, and periprocedural complication rates were pooled using SATA V.17.

RESULTS

Our analysis included five studies collectively enrolling 73 participants. Participant ages ranged from 52.9 to 65 years, with 64.4% being female. Aneurysms were wide-necked and predominantly located in the middle cerebral artery, basilar artery, and anterior cerebral artery. Previous treatments encompassed coiling, clipping, and the use of WEB devices. Our study found an overall adequate occlusion rate of 0.80 (95% CI 0.71-0.89), a complete occlusion rate of 0.39 (95% CI 0.28-0.50), and a neck remnant rate of 0.38 (95% CI 0.27-0.48). Periprocedural complications were reported at a rate of 0%, although heterogeneity was observed in this data. Notably, evidence of publication bias was identified in the reporting of periprocedural complication rates.

CONCLUSION

Our findings suggest that the WEB device is associated with favorable outcomes for treating recurrent wide-neck intracranial aneurysms.

Flow diverter retreatment for intracranial aneurysms: A meta-analysis of efficacy and feasibility

BACKGROUND

Recurrent intracranial aneurysm carries a risk of rupture and retreatment is often necessary. However, there is no consensus on the best retreatment modality of choice. Flow diverter has emerged as a promising option for this population in recent years. Given its high cost, patient selection to optimize outcomes is very important.

PURPOSE

To identify patient factors predisposing to failure of flow diverter retreatment.

METHOD

We conducted a systematic search on PubMed, Cochrane Library, Embase, Ovid/Medline, and ClinicalTrial.gov from 2000 to 2021. Studies regarding flow diverter retreatment of recurrent aneurysms were analyzed if they meet the inclusion criteria.

RESULTS

A total of twenty-six studies were identified. Among 374 patients retreated with flow diverters, about 0.86 [0.81; 0.92] were successfully occluded and only 0.06 [0.02; 0.10] had unfavorable neurological outcomes. Major complications included intracranial hemorrhage (n = 7), ischemic stroke or thromboembolic event (n = 12), and death (n = 2). In-stent stenosis was reported in 10 of the cases. Saccular aneurysms are associated with a higher occlusion rate while aneurysm location, size, status, and prior treatment modality have no significant impact on retreatment efficacy.

CONCLUSIONS

We demonstrated that flow diverter is an effective retreatment strategy except in patients with non-saccular aneurysms. It should be considered as a first-line option for patients with recurrent intracranial aneurysm.

Retreatment with a pipeline embolization device for recanalized aneurysms following stent-assisted coiling embolization

Background and purpose

Flow diverters have emerged as viable alternatives for the retreatment of recanalized aneurysms following stent-assisted coiling embolization. In this study, we aim to present our experience of retreatment for such aneurysms using the pipeline embolization device (PED).

Materials and methods

This case series presents a retrospective single-center analysis of patients with recanalized aneurysms who underwent retreatment using the PED between July 2019 and April 2023, subsequent to stent-assisted coiling embolization.

Results

The study includes five female patients, whose relevant clinical data were recorded. All patients had aneurysms located in the internal carotid artery, comprising two blood blister-like aneurysms and two giant aneurysms. Prior to the retreatment, two LVIS stents, two enterprise stents, and one solitaire stent were implanted. Among the five patients, one experienced a fatal post-operative subarachnoid hemorrhage, while two patients achieved complete embolization, and another patient achieved near-complete embolization during the last follow-up. Furthermore, one patient faced challenges during the placement of the PED and was unable to achieve successful deployment. We propose four overlapping relationships between a newly implanted PED and a previously deployed stent: (1) PED covering only the proximal end of the previous stent, (2) PED covering only the distal end of the previous stent, (3) PED covering both the proximal and distal ends of the previous stent, and (4) PED deployed within the previous stent. Antiplatelet therapy at our center involved daily dual therapy with aspirin (100 mg/day) and clopidogrel (75 mg/day) for at least 5 days before PED placement. Intra-arterial bolus administration of tirofiban (5 mcg/kg) was administered during or immediately after PED deployment, followed by a maintenance dose of 0.08 mcg/kg/min IV infusion for at least 24-48 h if necessary. Postprocedural dual antiplatelet therapy included clopidogrel (75 mg/day) for 6 months and aspirin (100 mg/day) for 12 months.

Conclusion

The findings of this study support the efficacy of the PED for the retreatment of recanalized aneurysms following stent-assisted coiling embolization.

Retreatment with a flow diverter for recurrent blood blister-like aneurysms after embolization: A single-center case series

Background and purpose

Treatment of blood blister-like aneurysms (BBAs) has been a significant challenge mainly due to their high recurrence rate even after stent-assisted coiling (SAC) embolization. This study aims to evaluate the safety and efficacy of treating recurrent BBAs after SAC with a flow diverter (FD).

Methods

A retrospective series of patients with recurrent BBAs who underwent the retreatment with the FD from June 2018 to December 2021 was included to analyze perioperative safety and immediate postoperative and follow-up outcomes.

Results

The study enrolled 13 patients with recurrent BBAs previously treated with SAC. Within previous stents, an FD was deployed for retreatment, including eight Tubridge FDs and five PEDs. The time interval between initial treatment and FD implantation was 14–90 days. A total of 11 cases were treated with a single FD alone; two cases were treated with further endovascular coiling embolization, followed by FD implantation. The angiographic follow-up (6–12 months) was available in 12 patients, and all 12 recurrent BBAs were completely occluded. No perioperative complication was detected, and no rebleeding was found during the clinical follow-up (6–36 months).

Conclusion

The use of the FD to manage recurrent BBAs after SAC is technically feasible, safe, and effective. The key to the success of the procedure is to ensure that the FD stent is fully open and has good apposition with the previously implanted stent.

Long-Term Characteristics of De Novo Bleb Formation at the Aneurysm Neck After Coil Embolization in Unruptured Cerebral Aneurysms

OBJECTIVE

De novo bleb formation at the aneurysm neck after coil embolization of unruptured intracranial aneurysms is a rarely observed type of recurrence. The aim of this study was to elucidate the clinical characteristics of recurrent aneurysms in the long-term period.

METHODS

Between January 2002 and December 2015, 290 unruptured intracranial aneurysms were treated with coil embolization at our institution. Patients who underwent retreatment due to aneurysm recurrence were divided into 2 patterns of recanalization: de novo bleb formation at the neck of a coiled sac (type DNV) and an enlarged residual cavity without de novo bleb formation (type non-DNV).

RESULTS

Twenty-seven patients with aneurysms (9.3%) underwent retreatment (type DNV, 7; type non-DNV, 20). The initial aneurysm size of type DNV aneurysms was significantly smaller than that of type non-DNV (6.1 ± 2.2 mm vs. 10.1 ± 3.6 mm; P < 0.01), and time to retreatment in type DNV was significantly longer than that in type non-DNV (9.4 ± 5.3 years vs. 2.0 ± 2.0 years; P < 0.01). Two type DNV basilar artery (BA) aneurysms ruptured after a few years; however, the other type DNV aneurysms, including 4 anterior circulation aneurysms (including the internal carotid artery), were observed to grow gradually without rupture for >10 years until retreatment.

CONCLUSIONS

De novo bleb formation at the neck of a coiled sac emerges with insidious growth during long-term follow-up. Constant caution should be exercised, even in cases of small- and medium-sized anterior circulation aneurysms. A risk of rupture risk may be anticipated, especially in BA lesions.

The Safety and Effectiveness of the Contour Neurovascular System (Contour) for the Treatment of Bifurcation Aneurysms: The CERUS Study

BACKGROUND

The Contour is a novel intra-aneurysmal flow disrupting device to treat intracranial aneurysms.

OBJECTIVE

To evaluate the safety and effectiveness of the Contour device for treatment of nonruptured intracranial bifurcation aneurysms through a prospective, multicenter, single-arm study.

METHODS

Thirty-four patients were enrolled. Primary end points were successful occlusion at 6 mo for efficacy and any major stroke or nonaccidental death up to 30 d or major disabling stroke within 6 mo for safety. Secondary end points were occlusion at 12 mo, retreatment rate, procedure time, and procedure-related/device-related adverse events. Procedural and follow-up imaging was reviewed by an independent core laboratory. Adverse events were reviewed and adjudicated by a clinical events committee.

RESULTS

In total, 32 of 34 aneurysms were successfully implanted and, 2 of 34 in the intention-to-treat (ITT) group did not receive the Contour and were excluded from follow-up after 30 d. In addition, 2 of 32 were lost to angiographic follow-up and regarded as treatment failure. The primary safety end point was met in 2 patients in the ITT group. In the perprotocol (PP) group, complete occlusion was seen in 14 of 32 (44%) at 6 mo and 22 of 32 (69%) at 12 mo. Adequate occlusion (Raymond-Roy [RR] 1 and 2) was reached in 84% at a last available follow-up. One patient from the ITT group and 1 from the PP group received additional treatment during follow-up.

CONCLUSION

The Contour seems to be both safe and effective in the treatment of intracranial bifurcation aneurysms.

Postprocedural Thrombosis following Endovascular Treatment of Intracranial Aneurysm with Flow Diverters or Coiling: A Histologic Study

Endovascular treatment of aneurysms with flow diverters or coiling is sometimes complicated by intraprocedural or postprocedural thrombosis along or within the devices. Thrombus composition and structure associated with such complications may provide insights into mechanisms of thrombus formation and clinical strategies to remove the thrombus. We present a retrospective histopathologic study of 4 patients who underwent mechanical thrombectomy due to acute occlusion of either implanted flow diverter devices or along coils during the treatment of intracranial aneurysm.

Retreatment With Flow Diverters and Coiling for Recurrent Aneurysms After Initial Endovascular Treatment: A Propensity Score-Matched Comparative Analysis

Background: Flow diverters and conventional coiling are established modalities for the retreatment of intracranial recurrent aneurysms after initial endovascular treatment. We aimed to compare the efficacy of these techniques. Methods: We retrospectively analyzed data for patients with recurrent aneurysms after initial endovascular treatment retreated in our center with either a pipeline embolization device (PED) or conventional coil embolization from January 2012 to July 2020. We performed 1:2 propensity score matching (PSM) using the nearest neighbor method. We controlled for: initial treatment strategy, aneurysm size, neck diameter, symptom presentation, history of aneurysm rupture, age, sex, fusiform-dissecting aneurysm, bifurcation aneurysm, and aneurysm location. The clinical and morphological factors of all patients at initial treatment and the angiographic and clinical results at the second treatment were collected and compared between the propensity-matched pairs. Results: A total of 105 intracranial aneurysms were identified; 18 patients (17.1%) were treated with a PED, and 87 (82.9%) were treated via conventional coil embolization. PSM resulted in 12 matched pairs (12 patients in the PED group and 24 in the coiling group). There was no significant difference of ischemic and hemorrhagic complications between the groups, the obliteration rate of branches covered by stent, or modified Rankin Scale scores at the last clinical follow-up. Importantly, the retreatment strategy in the PED group provided significantly different results vs. the coiling group (P < 0.001), with a lower recurrence rate (0.0 vs. 29.2%, respectively; P = 0.037). However, the procedural failure rate and the parent artery stenosis were more frequently in PED group compared with coiling group (both were 16.7 vs. 0.0%; P = 0.040). Conclusions: Endovascular retreatment for recurrent aneurysms after initial endovascular treatment might be safe and effective. Flow diverters might be associated with reduced risk of recanalization and an increased risk of procedural failure and mild parent artery stenosis.

Flow diverter stents in the treatment of recanalized intracranial aneurysms

BACKGROUND

We assessed the safety and efficacy of flow diverter stents (FDSs) in the treatment of recanalized or residual intracranial aneurysms treated endovascularly.

MATERIALS & METHODS

Patients whose recanalized or residual aneurysms were treated with FDSs in five tertiary hospitals were reviewed retrospectively. The patients' demographic data, aneurysm characteristics, types of previous treatment, and clinical complications, or serious adverse events associated with FDSs, as well as the results of neurological and angiographic follow-up assessments, were recorded.

RESULTS

Eighty-six patients (37 males) with 87 aneurysms were included in this study. Eighty (91.9%) aneurysms were in the anterior and seven (8.1%) in the posterior circulation. The initial treatment methods were the primary coiling or balloon remodeling technique in 69 (79.3%) and stent-assisted coiling in 18 (20.7%) aneurysms. The endovascular procedure was successful in all patients. Complications occurred in four patients, for a total complication rate of 4.6%. A technical complication developed in one patient (1.2%). An in-stent thrombosis treated with tirofiban was seen in two cases. Late in-stent stenosis exceeding 50% was treated with balloon angioplasty in one patient. The mean length of follow-up was 21.0 months. The first angiographic follow-up (3-6 months) revealed the complete occlusion of 74 aneurysms (85.1%). While 76 aneurysms (87.4%) were occluded at the last angiographic follow-up (mean: 26.0 months), 11 aneurysms (12.6%) were still filling. Morbimortality was zero.

CONCLUSION

The drawback of endovascular treatment is aneurysmal remnants or recurrences, which is safely and durably amenable to flow diversion.

Intracranial aneurysms managed by parent artery reconstruction using Tubridge: Study protocol for a prospective, multicenter, post-market clinical trial

BACKGROUND

As a new endovascular reconstruction technique, flow diverter (FD) shows excellent efficacy and safety for treatment of intracranial aneurysms. In a previous multicenter, randomized, controlled, pre-market study, Tubridge FD showed remarkably higher complete occlusion rate compared with traditional stent-assisted coiling. However, a nonsignificant higher complication rate in the Tubridge group was noted. Considering the learning curve, the safety, and long-term outcomes of Tubridge FD should be verified in new prospective, real world, multicenter, post-market trials.

METHODS

This study is a prospective, multicenter, single-arm, post-market clinical trial that evaluates the safety and efficacy of Tubridge in the treatment of patients with intracranial aneurysms by reconstructing parent artery. We expect 200 participants who meet the inclusion and exclusion criteria to be included. Clinical information and angiographic results (Raymond-Roy grading scale, RRGS) will be recorded objectively. The primary endpoint will be the complete occlusion rate of the target aneurysm (RRGS 1) at 12-month follow-up. Secondary endpoints will include the adequate occlusion rate (RRGS 1 & 2) and the rate of major in-stent stenosis (>50%) at 12-month follow-up, technique success rate, changes of modified Rankin Scale before and after the procedure, the rate of aneurysm related disability, neurological mortality, and all-cause mortality within follow-up period.

DISCUSSION

This post-market, prospective trial may offer more information on the safety and long-term outcomes of Tubridge FD. When the study is complete, the results may provide us a new strategy for the treatment of intracranial aneurysms.Trial registration: WHO-Chinese Clinical Trial Registry: ChiCTR2000032282.