Endovascular Therapy for Ruptured Vertebral Artery Dissecting Aneurysms: Results from Nationwide, Retrospective, Multi-Center Registries in Japan (JR-NET3)

Strategies and outcomes of endovascular treatment of posterior inferior cerebellar artery aneurysms: a single center experience

To explore safe and reliable strategies and outcomes of endovascular procedures in the treatment of posterior inferior cerebellar artery (PICA) aneurysms. Retrospectively reviewed and analyzed the cases of PICA aneurysms that undergone endovascular therapy from July 2017 through January 2022 in our neurosurgical center, as well as outcomes of long-term follow-up. Total 24 cases were enrolled. Majority of the PICA aneurysms (87.5%, 21/24) presented initially with subarachnoid hemorrhage (SAH) and only 3 cases were not ruptured when they were clinically diagnosed as PICA aneurysms. The patients were endovascularly given either aneurysm occlusion with selective coils (12 cases), embolization of aneurysms and parent arteries (7 cases: 3 cases with coils and 4 cases with Onyx liquid embolic agent), or stent-assisted coiling of the aneurysms (5 cases). One patient, who had comorbidity of intracranial hemorrhage and severe cerebral vasospasm, declined further post-surgery therapy, and discharged from the hospital with anticipation of poor outcome. The rest 23 patients were followed up for 3-24 months with a recurrence rate of 17.4% (4/23). Endovascular procedure of embolizing PICA aneurysms with selective coils or stent-assisted coils is feasible, safe, and reliable. Simplified embolization of the aneurysms or occlusion of the parent artery is recommended as the first choice for the ruptured and bleeding PICA aneurysms.

Endovascular Treatment for Intracranial Artery Dissections in Posterior Circulation

Intracranial artery dissections (IADs), although uncommon, are an important cause of cerebral infarction and subarachnoid hemorrhage (SAH). Some IADs can heal spontaneously after reconstitution of the vessel lumen with excellent prognosis. Meanwhile, others can progress to stroke that requires treatment. The incidence of IAD in the posterior circulation is higher than that in the anterior circulation. Anterior circulation dissections are more likely to develop into ischemia and posterior circulation lesions into hemorrhage. The mortality rate after IAD among patients with SAH is 19%-83%. Further, the mortality rate of IAD without SAH is 0%-3%. Patients with SAH commonly undergo surgery or receive neuroendovascular treatment (EVT) to prevent rebleeding. However, the treatment of IADs is empirical in the absence of data from randomized controlled trials. Recently, EVT has emerged and is considered for IADs because of its less invasiveness and perceived low rates of procedure-related morbidity with good efficacy. EVT strategies can be classified into deconstructive (involving sacrifice of the parent artery) and reconstructive (preserving blood flow via the parent vessel) techniques. In particular, the number of reports on reconstructive techniques is increasing. However, a reconstructive technique for ruptured IADs has not yet been established. This review aimed to provide an overview of IADs in the posterior circulation managed with EVT by performing a literature search.

Stent-Assisted Coil Embolization Versus Flow-Diverting Stent in Unruptured Vertebral Artery Dissecting Aneurysms: Efficacy and Safety Comparison

BACKGROUND

Reconstructive strategies for unruptured vertebral artery dissecting aneurysms (VADAs) have increasingly relied on newly developed endovascular devices. However, their clinical performance metrics are seldom reported.

OBJECTIVE

To compare stent-assisted coil embolization (SACE) and flow-diverting stent (FDS) deployment as treatments for unruptured VADAs, focusing on efficacy and safety.

METHODS

A total of 72 VADAs were submitted to SACE (n = 48) or FDS (n = 24) between April 2009 and September 2021. We reviewed medical records and radiological data to assess efficacy and safety outcomes by method, building an inverse probability of treatment-weighted (IPTW) logistic regression model and conducting survival analyses.

RESULTS

Ultimately, 24 aneurysms (33.3%) showed signs of recanalization (major, 14; minor, 10) at 6-month follow-up. Initially determined 6-month rates of overall (SACE, 31.2%; FDS, 41.7%) and major (SACE, 20.8%; FDS, 16.7%) recanalization did not differ significantly by modality; but in the IPTW logistic regression model, adjusted for aneurysm morphology, major recanalization at 6 months was lower for the FDS (vs SACE) subset (odds ratio = 0.196; P = .027). Likewise, the cumulative rate of major recanalization was more favorable for the FDS (vs SACE) subset (hazard ratio = 0.291; P = .048) in IPTW Cox proportional hazards model adjusted for aneurysm morphology. Modality-based assessments of procedural and delayed complications were similar.

CONCLUSION

Both reconstructive VADA interventions are safe and effective by adjusting treatment modality depending on the angioanatomic configuration. However, follow-up data after treatment proved more favorable for FDS deployment than for SACE in limiting major recanalization. Case-controlled studies of more sizeable cohorts are needed for corroboration.

Comparison of Parent Artery Occlusion and Stent-Assisted Treatments in Ruptured Vertebral Artery Dissecting Aneurysms

OBJECTIVE

To assess clinical outcomes of ruptured vertebral artery dissecting aneurysms, focusing on comparing parent artery occlusion (PAO) with stent-assisted treatments, and to identify risk factors for unfavorable outcomes and postprocedural complications.

METHODS

This retrospective review included 36 ruptured vertebral artery dissecting aneurysms treated between February 2009 and April 2020. Treatment modalities included PAO without stent and stent-assisted treatments. Stent-assisted treatments included PAO with posterior inferior cerebellar artery (PICA) stenting and stent-assisted coiling. Univariate and multivariate analyses were conducted to evaluate risk factors for unfavorable outcomes and postprocedural complications.

RESULTS

Patients were treated with PAO only (24, 66.7%), PAO with PICA stenting (4, 11.1%), and PAO with stent-assisted coiling (8, 22.2%). There were only fusiform aneurysms with PICA involvement in the PAO with PICA stenting group. In the stent-assisted coiling group, 4 aneurysms incorporated PICA, and 4 aneurysms involved dominant vertebral artery. Old age (odds ratio [OR] = 1.25, 95% confidence interval [CI] = 1.01-1.56, P = 0.044) and poor Hunt-Hess grade (OR = 537.99, 95% CI = 6.73-42994.1, P = 0.005) were significantly associated with unfavorable clinical outcomes after a mean follow-up of 37.5 ± 32.8 months. Fusiform dilatation shape (OR = 15.97, 95% CI = 1.52-167.38, P = 0.021) and PICA involvement (OR = 13.71, 95% CI = 1.29-145.89, P = 0.030) were independent risk factors for ischemic complications.

CONCLUSIONS

Unfavorable clinical outcomes were significantly related to old age and poor Hunt-Hess grade. There were no significant differences between treatment groups in clinical outcomes or ischemic complications. Stent-assisted treatments might be effective and safe methods for ruptured vertebral artery dissecting aneurysms.

Clinical and radiological risk factors for rupture of vertebral artery dissecting aneurysm: significance of the stagnation sign

OBJECTIVE

The aim of this study was to investigate the clinical and radiological factors associated with the rupture of a vertebral artery dissecting aneurysm (VADA) and to evaluate whether the stagnation sign is a significant risk factor for rupture of VADA.

METHODS

Clinical and radiological variables of 117 VADAs treated in a tertiary hospital from September 2008 to December 2020 were retrospectively reviewed. The stagnation sign is defined as the finding of contrast agent remaining in the lesion until the venous phase of angiography. Univariate and multivariate analyses were executed to reveal the associations between rupture status and VADA characteristics.

RESULTS

The rate of ruptured VADAs was 29.1% (34 of 117) and the stagnation sign was observed in 39.3% (46 of 117). Fusiform shape (OR 5.105, 95% CI 1.591-16.383, p = 0.006), irregular surface (OR 4.200, 95% CI 1.412-12.495, p = 0.010), posterior inferior cerebellar artery (PICA) involvement (OR 3.788, 95% CI 1.288-11.136, p = 0.016), and the stagnation sign (OR = 3.317, 95% CI 1.131-9.732, p = 0.029) were significantly related to rupture of VADA in multivariate logistic regression analysis.

CONCLUSIONS

This study showed that fusiform shape, irregular surface, PICA involvement, and the stagnation sign may be independent risk factors for the rupture of VADA. Therefore, when the potential risk factors are observed in unruptured VADA, more aggressive treatment rather than follow-up or medical therapy may be considered.

Mobile endovascular therapy for acute treatment of ruptured vertebral artery dissecting aneurysm in multiple hospitals

BACKGROUND

The patients with ruptured vertebral artery dissecting aneurysm (rVADA) should be treated as early as possible because VADA carries extremely high risk of rebleeding in the acute phase. We have established a mobile endovascular strategy for the patients with rVADA between our flagship center and its affiliated local hospitals. We introduced and reviewed our mobile endovascular therapy in this study.

METHODS

We retrospectively evaluated 98 consecutive patients who underwent endovascular surgery for rVADA from 2000 to 2018 at our institution or five affiliated hospitals. When each patient was initially transported to the local affiliated hospitals, neuroendovascular surgeons traveled directly to the affiliated hospital from the flagship center in order to treat the patient there. Clinical outcomes using modified Rankin Scale at 6 months after treatment, radiological results, and procedure-related complications were reviewed to justify our mobile endovascular strategy.

RESULTS

All aneurysms were cured successfully by internal trapping. Favorable outcome was achieved in 61 patients (62.2%) even though 53 patients (54.1%) had presented with severe subarachnoid hemorrhage. Overall mortality rate, treatment-related mortality rate, and treatment related complication rate were 18.4% (18/98), 0%, and 16% (16/98), respectively. There were no differences in clinical and radiological outcomes between the patients treated in the flagship center and those who treated in the affiliated hospitals. Treatment in the affiliated hospital was not a predictive factor of unfavorable outcome in our multivariate analysis, and elderly age (≥ 60) was negatively associated with favorable outcome.

CONCLUSIONS

Our results prove the efficacy and safety of mobile endovascular therapy for the treatment of rVADA in the ultra-acute stage. Mobile endovascular therapy may work well in the acute treatment of rVADAs in the certain circumstance.

ESO guideline for the management of extracranial and intracranial artery dissection

The aim of the present European Stroke Organisation guideline is to provide clinically useful evidence-based recommendations on the management of extracranial artery dissection (EAD) and intracranial artery dissection (IAD). EAD and IAD represent leading causes of stroke in the young, but are uncommon in the general population, thus making it challenging to conduct clinical trials and large observational studies. The guidelines were prepared following the Standard Operational Procedure for European Stroke Organisation guidelines and according to GRADE methodology. Our four recommendations result from a thorough analysis of the literature comprising two randomized controlled trials (RCTs) comparing anticoagulants to antiplatelets in the acute phase of ischemic stroke and twenty-six comparative observational studies. In EAD patients with acute ischemic stroke, we recommend using intravenous thrombolysis (IVT) with alteplase within 4.5 hours of onset if standard inclusion/exclusion criteria are met, and mechanical thrombectomy in patients with large vessel occlusion of the anterior circulation. We further recommend early endovascular or surgical intervention for IAD patients with subarachnoid hemorrhage (SAH). Based on evidence from two phase 2 RCTs that have shown no difference between the benefits and risks of anticoagulants versus antiplatelets in the acute phase of symptomatic EAD, we strongly recommend that clinicians can prescribe either option. In post-acute EAD patients with residual stenosis or dissecting aneurysms and in symptomatic IAD patients with an intracranial dissecting aneurysm and isolated headache, there is insufficient data to provide a recommendation on the benefits and risks of endovascular/surgical treatment. Finally, nine expert consensus statements, adopted by 8 to 11 of the 11 experts involved, propose guidance for clinicians when the quality of evidence was too low to provide recommendations. Some of these pertain to the management of IAD (use of IVT, endovascular treatment, and antiplatelets versus anticoagulation in IAD with ischemic stroke and use of endovascular or surgical interventions for IAD with headache only). Other expert consensus statements address the use of direct anticoagulants and dual antiplatelet therapy in EAD-related cerebral ischemia, endovascular treatment of the EAD/IAD lesion, and multidisciplinary assessment of the best therapeutic approaches in specific situations.

Target Embolization of Dilated Post-PICA Segment for Ruptured PICA-Involved Type Vertebral Artery Dissecting Aneurysm

Objective

In parent artery occlusion (PAO) for ruptured vertebral artery dissecting aneurysms (RVADA), target embolization using coils in a short segment to occlude only the vasodilated area containing the rupture point is selected as a first-choice procedure at our institute. We focused on RVADA involving the posterior inferior cerebellar artery (PICA) and evaluated the treatment results.

Methods

This study consisted of eight cases with RVADA involving the PICA which were treated between October 2007 and January 2020. Based on radiological findings such as the bleb, the rupture points were located at the affected vertebral artery (VA) distal to PICA in all cases. Target embolization, by which only coiling at the dilated segment distal to the VA was performed. We aimed to preserve blood flow to the PICA. The incidence and extent of medullary infarctions, and neurological outcome were retrospectively assessed.

Results

Regarding the diameter of bilateral VA, there were no differences in six cases while the affected VA with RVADA were larger in the remaining two cases. PICA was preserved in all cases but one in which occlusion of complementary PICA was observed. Postoperative medullary infarction was not noted. There was no rebleeding during the follow-up period. However, recanalization of the VA was observed in four cases and additional coil embolization was performed. All patients were discharged with a good outcome (modified Rankin Scale [mRS] 0; seven patients, mRS 2; one patient).

Conclusion

Target embolization preserving the PICA in PICA-involved type RVADA was considered to be an effective treatment method for cases whose rupture point was located in the VA distal to PICA orifice.

Endovascular treatment for ruptured vertebral dissecting aneurysms involving PICA: Reconstruction or deconstruction? Experience from 16 patients

OBJECTIVE

Ruptured vertebral dissecting aneurysms (VDAs) with posterior inferior cerebellar artery (PICA) involved require an optimal method to isolate the dissection and prevent the symptomatic infraction. This study aims to present our experience with both parent artery occlusion (PAO) and stent-assisted coiling (SAC), and provide a favorable strategy to the management of ruptured VDAs with PICA involved.

METHODS

We retrospectively reviewed patients with subarachnoid hemorrhage in our database from March 2013 to December 2018, suffering from dissecting aneurysms of the intradural vertebral arteries and endovascularly treated. A total of 16 cases with PICA involved were included. Basic information, aneurysm characteristics, procedure related complications and outcomes of patients were analyzed.

RESULTS

10 (62.5%) aneurysms were managed with PAO containing 3 proximal occlusion and 8 targeted-trapping preserved the PICA. 5 (31.3%) aneurysms were treated with SAC and one 6.3%) treated with vertebral artery to PICA stenting and trapping. Two (12.5%) patients died in the acute phase. Good clinical outcomes (modified Rankin Scale 0 to 3) were observed in 13(81.5%) cases in 30 days follow-up. PICA territory infraction was happened in one patient without any dysfunction. Favorable occlusion was observed in 9 of 12 (75%) which were free of further treatment.

CONCLUSIONS

For patients with good contralateral circulation, PAO could be a first line management for ruptured VDAs with PICA involved. Targeted-trapping with either reserved PICA or proximal occlusion with moderate coiling in aneurysm are promising modalities to prevent severe PICA infraction.

Treatment Outcomes of Stent-Assisted Coil Embolization for Ruptured Vertebral Artery Dissecting Aneurysms: The Preservation of Branches May Improve the Prognosis

Objective

Subarachnoid hemorrhage due to ruptured vertebral artery dissecting aneurysm (rVADA) is associated with a high frequency of acute rebleeding and requires early treatment following onset. Parent artery occlusion (PAO) or stent-assisted coiling (SAC) embolization is selected as a treatment option according to the individual patient condition. This report is a retrospective examination evaluating the treatment outcomes for rVADA.

Methods

The subjects were 20 rVADA patients (16 men and 4 women) who underwent endovascular treatment at our institution. The mean patient age was 52.9 years. Ten patients each were allocated to the PAO group and SAC group. We evaluated and compared the following parameters: presence of hemorrhagic complications, presence of ischemic complications, requirement of retreatment, and Glasgow Outcome Scale (GOS) after 90 days.

Results

The reasons for selecting SAC were contralateral occlusion or a small diameter in three patients, the posterior inferior cerebellar artery (PICA) involvement in three patients, perforating artery from dissected lesion in five patients, and anterior spinal artery in one patient. There was no rebleeding in any patient. Symptomatic ischemic complications were observed in four patients in the PAO group and in one in the SAC group. Hyper-intense lesions in the brainstem on MRI DWI were noted in five patients in PAO group and in one in the SAC group. Retreatment was required for three patients in the PAO group and for four in the SAC group. Favorable outcomes (GOS 4, 5) after 90 days were observed for three patients in the PAO group and for eight patients in the SAC group (p = 0.0257).

Conclusion

SAC that can preserve branches is a useful treatment option for rVADA. Further studies on a greater number of subjects are required to establish the optimal dose of antiplatelet agents and anticoagulants, and for stent selection.

Stent-Jack Technique for Ruptured Vertebral Artery Dissecting Aneurysm Involving the Origin of Posterior Inferior Cerebellar Artery

We herein report a case of a ruptured vertebral artery dissecting aneurysm involving the origin of the posterior inferior cerebellar artery that was treated using the stent-jack technique. After parent artery occlusion of the distal vertebral artery, stenting of the posterior inferior cerebellar artery was performed. Further coiling was needed because distal vertebral artery recanalization occurred due to transformation of the coil mass. The stent-jack technique for a ruptured vertebral artery dissecting aneurysm involving the origin of the posterior inferior cerebellar artery is effective; however, careful attention to recanalization after stenting is needed due to transformation of the coil mass.

The Current Status of Endovascular Treatment for Extracranial Steno-occlusive Diseases in Japan: Analysis Using the Japanese Registry of Neuroendovascular Therapy 3 (JR-NET3)

Endovascular treatment of extracranial steno-occlusive lesions is an alternative to direct surgery. There is no consensus regarding the natural course and standard treatment of these lesions. The aim of this study was to identify the current status of endovascular treatment for extracranial steno-occlusive lesions. A total of 1154 procedures for extracranial steno-occlusive lesions, except for internal carotid artery stenosis, were collected from the Japanese Registry of Neuroendovascular Therapy 3 (JR-NET3). Atherosclerotic lesions were most frequent (1021 patients, 88.5%). Endovascular treatment was performed for 456 (39.5%) patients with subclavian artery, 349 (30.2%) with extracranial vertebral artery, 172 (14.9%) with the origin of common carotid artery, and 38 (3.3%) with innominate artery stenosis; the overall technical success rate was 98.0%. Percutaneous transluminal angioplasty was performed in 307 patients (26.6%) and stenting in 838 (72.6%). An embolic protection device (EPD) was used in 571 patients (49.5%), and procedure under general anesthesia was performed in 168 (14.6%). Preoperative antiplatelet therapy was administered in 1091 procedures (94.5%). A good outcome was obtained for 962 patients (83.4%). Complications were observed in 89 patients (7.7%). The procedure under general anesthesia was statistically significant factors (P <0.01), and also after multivariable adjustment (odds ratio 2.29; 95% confidence interval 1.25–4.17; P <0.01). Comparisons between JR-NET3 and previous cohorts (JR-NET1&2), the utilization of EPD and complications increased significantly, and the type of antiplatelet therapy changed markedly. Based on the results of this study, endovascular treatment for extracranial steno-occlusive lesions is relatively safe. Further prospective studies are necessary to validate the beneficial effects.