Multimodality treatment for brain arteriovenous malformation in Mainland China: design, rationale, and baseline patient characteristics of a nationwide multicenter prospective registry

Association of the combined stereotactic radiosurgery and embolization strategy and long-term outcomes in brain arteriovenous malformations with a volume ≤10 mL: a nationwide multicenter observational prospective cohort study

BACKGROUND

To compare the long-term outcomes of stereotactic radiosurgery (SRS) with or without prior embolization in brain arteriovenous malformations (AVMs) (volume ≤10 mL) for which SRS is indicated.

METHODS

Patients were recruited from a nationwide multicenter prospective collaboration registry (the MATCH study) between August 2011 and August 2021, and categorized into combined embolization and SRS (E+SRS) and SRS alone cohorts. We performed propensity score-matched survival analysis to compare the long-term risk of non-fatal hemorrhagic stroke and death (primary outcomes). The long-term obliteration rate, favorable neurological outcomes, seizure, worsened mRS score, radiation-induced changes, and embolization complications were also evaluated (secondary outcomes). Hazard ratios (HRs) were calculated using Cox proportional hazards models.

RESULTS

After study exclusions and propensity score matching, 486 patients (243 pairs) were included. The median (IQR) follow-up duration for the primary outcomes was 5.7 (3.1-8.2) years. Overall, E+SRS and SRS alone were similar in preventing long-term non-fatal hemorrhagic stroke and death (0.68 vs 0.45 per 100 patient-years; HR=1.46 (95% CI 0.56 to 3.84)), as well as in facilitating AVM obliteration (10.02 vs 9.48 per 100 patient-years; HR=1.10 (95% CI 0.87 to 1.38)). However, the E+SRS strategy was significantly inferior to the SRS alone strategy in terms of neurological deterioration (worsened mRS score: 16.0% vs 9.1%; HR=2.00 (95% CI 1.18 to 3.38)).

CONCLUSIONS

In this observational prospective cohort study, the combined strategy of E+SRS does not show substantial advantages over SRS alone. The findings do not support pre-SRS embolization for AVMs with a volume ≤10 mL.

A comprehensive analysis of patients with cerebral arteriovenous malformation with headache: assessment of risk factors and treatment effectiveness

BACKGROUND

Due to the high mortality and disability rate of intracranial hemorrhage, headache is not the main focus of research on cerebral arteriovenous malformation (AVM), so research on headaches in AVM is still scarce, and the clinical understanding is shallow. This study aims to delineate the risk factors associated with headaches in AVM and to compare the effectiveness of various intervention treatments versus conservative treatment in alleviating headache symptoms.

METHODS

This study conducted a retrospective analysis of AVMs who were treated in our institution from August 2011 to December 2021. Multivariable logistic regression analysis was employed to assess the risk factors for headaches in AVMs with unruptured, non-epileptic. Additionally, the effectiveness of different intervention treatments compared to conservative management in alleviating headaches was evaluated through propensity score matching (PSM).

RESULTS

A total of 946 patients were included in the analysis of risk factors for headaches. Multivariate logistic regression analysis identified that female (OR 1.532, 95% CI 1.173-2.001, p = 0.002), supply artery dilatation (OR 1.423, 95% CI 1.082-1.872, p = 0.012), and occipital lobe (OR 1.785, 95% CI 1.307-2.439, p < 0.001) as independent risk factors for the occurrence of headaches. There were 443 AVMs with headache symptoms. After propensity score matching, the microsurgery group (OR 7.27, 95% CI 2.82-18.7 p < 0.001), stereotactic radiosurgery group(OR 9.46, 95% CI 2.26-39.6, p = 0.002), and multimodality treatment group (OR 8.34 95% CI 2.87-24.3, p < 0.001) demonstrate significant headache relief compared to the conservative group. However, there was no significant difference between the embolization group (OR 2.24 95% CI 0.88-5.69, p = 0.091) and the conservative group.

CONCLUSIONS

This study identified potential risk factors for headaches in AVMs and found that microsurgery, stereotactic radiosurgery, and multimodal therapy had significant benefits in headache relief compared to conservative treatment. These findings provide important guidance for clinicians when developing treatment options that can help improve overall treatment outcomes and quality of life for patients.

Most Promising Approaches to Improve Brain AVM Management: ARISE I Consensus Recommendations

Brain arteriovenous malformations (bAVMs) are complex, and rare arteriovenous shunts that present with a wide range of signs and symptoms, with intracerebral hemorrhage being the most severe. Despite prior societal position statements, there is no consensus on the management of these lesions. ARISE (Aneurysm/bAVM/cSDH Roundtable Discussion With Industry and Stroke Experts) was convened to discuss evidence-based approaches and enhance our understanding of these complex lesions. ARISE identified the need to develop scales to predict the risk of rupture of bAVMs, and the use of common data elements to perform prospective registries and clinical studies. Additionally, the group underscored the need for comprehensive patient management with specialized centers with expertise in cranial and spinal microsurgery, neurological endovascular surgery, and stereotactic radiosurgery. The collection of prospective multicenter data and gross specimens was deemed essential for improving bAVM characterization, genetic evaluation, and phenotyping. Finally, bAVMs should be managed within a multidisciplinary framework, with clinical studies and research conducted collaboratively across multiple centers, harnessing the collective expertise and centralization of resources.

Comparison of conservative management, microsurgery only, and microsurgery with preoperative embolization for unruptured arteriovenous malformations: A propensity score weighted prospective cohort study

AIMS

To compare the efficacy and deficiency of conservative management (CM), microsurgery (MS) only, and microsurgery with preoperative embolization (E + MS) for unruptured arteriovenous malformations (AVMs).

METHODS

We prospectively included unruptured AVMs undergoing CM, MS, and E + MS from our institution between August 2011 and August 2021. The primary outcomes were long-term neurofunctional outcomes and hemorrhagic stroke and death. In addition to the comparisons among CM, MS, and E + MS, E + MS was divided into single-staged hybrid and multi-staged E + MS for further analysis. Stabilized inverse probability of treatment weighting using propensity scores was applied to control for confounders by treatment indication across the three groups.

RESULTS

Of 3758 consecutive AVMs admitted, 718 patients were included finally (266 CM, 364 MS, and 88 E + MS). The median follow-up duration was 5.4 years. Compared with CM, interventions (MS and E + MS) were associated with neurological deterioration. MS could lower the risk of hemorrhagic stroke and death. Multi-staged E + MS was associated with neurological deterioration and higher hemorrhagic risks compared with MS, but the hybrid E + MS operation significantly reduced the hemorrhage risk.

CONCLUSION

In this study, unruptured AVMs receiving CM would expect better neurofunctional outcomes but bear higher risks of hemorrhage than MS or E + MS. The single-staged hybrid E + MS might be promising in reducing inter-procedural and subsequent hemorrhage.

Current perspectives and trends in the treatment of brain arteriovenous malformations: a review and bibliometric analysis

Background

Currently, there is a lack of intuitive analysis regarding the development trend, main authors, and research hotspots in the field of cerebral arteriovenous malformation treatment, as well as a detailed elaboration of possible research hotspots.

Methods

A bibliometric analysis was conducted on data retrieved from the Web of Science core collection database between 2000 and 2022. The analysis was performed using R, VOSviewer, CiteSpace software, and an online bibliometric platform.

Results

A total of 1,356 articles were collected, and the number of publications has increased over time. The United States and the University of Pittsburgh are the most prolific countries and institutions in the field. The top three cited authors are Kondziolka D, Sheehan JP, and Lunsford LD. The Journal of Neurosurgery and Neurosurgery are two of the most influential journals in the field of brain arteriovenous malformation treatment research, with higher H-index, total citations, and number of publications. Furthermore, the analysis of keywords indicates that "aruba trial," "randomised trial," "microsurgery," "onyx embolization," and "Spetzler-Martin grade" may become research focal points. Additionally, this paper discusses the current research status, existing issues, and potential future research directions for the treatment of brain arteriovenous malformations.

Conclusion

This bibliometric study comprehensively analyses the publication trend of cerebral arteriovenous malformation treatment in the past 20 years. It covers the trend of international cooperation, publications, and research hotspots. This information provides an important reference for scholars to further study cerebral arteriovenous malformation.

Long-term outcomes of microsurgery and stereotactic radiosurgery as the first-line treatment for arteriovenous malformations: a propensity score-matched analysis using nationwide multicenter prospective registry data

BACKGROUND

This study aimed to compare the risk and benefit profile of microsurgery (MS) and stereotactic radiosurgery (SRS) as the first-line treatment for unruptured and ruptured arteriovenous malformations (AVMs).

MATERIALS AND METHODS

The authors included AVMs underwent MS or SRS as the first-line treatment from a nationwide prospective multicenter registry in mainland China. The authors used propensity score-matched methods to balance baseline characteristics between the MS and SRS groups. The primary outcomes were long-term hemorrhagic stroke or death, and the secondary outcomes were long-term obliteration and neurological outcomes. Subgroup analyses and sensitivity analyses with different study designs were performed to confirm the stability of our findings.

RESULTS

Of the 4286 consecutive AVMs in the registry from August 2011 to December 2021; 1604 patients were eligible. After matching, 244 unruptured and 442 ruptured AVMs remained for the final analysis. The mean follow-up duration was 7.0 years in the unruptured group and 6.1 years in the ruptured group. In the comparison of primary outcomes, SRS was associated with a higher risk of hemorrhagic stroke or death both in the unruptured and ruptured AVMs (unruptured: hazard ratio 4.06, 95% CI: 1.15-14.41; ruptured: hazard ratio 4.19, 95% CI: 1.58-11.15). In terms of the secondary outcomes, SRS was also observed to have a significant disadvantage in long-term obliteration [unruptured: odds ratio (OR) 0.01, 95% CI: 0.00-0.04; ruptured: OR 0.09, 95% CI: 0.05-0.15]. However, it should be noted that SRS may have advantages in preventing neurofunctional decline (unruptured: OR 0.56, 95% CI: 0.27-1.14; ruptured: OR 0.41, 95% CI: 0.23-0.76). The results of subgroup analyses and sensitivity analyses were consistent in trend but with slightly varied powers.

CONCLUSIONS

This clinical practice-based real-world study comprehensively compared MS and SRS for AVMs with long-term outcomes. MS is more effective in preventing future hemorrhage or death and achieving obliteration, while the risk of neurofunctional decline should not be ignored.

Recurrence of Cerebral Arteriovenous Malformation Following Complete Obliteration Through Endovascular Embolization

Arteriovenous malformation (AVM) recurrence after embolization was rarely reported. This study aimed to explore the potential risk factors of recurrence in angiographically obliterated AVMs treated with endovascular embolization. This study reviewed AVMs treated with embolization only in a prospective multicenter registry from August 2011 to December 2021, and ultimately included 92 AVMs who had achieved angiographic obliteration. Recurrence was assessed by follow-up digital subtraction angiography (DSA) or magnetic resonance imaging (MRI). Hazard ratios (HRs) with 95% confidence intervals were calculated using Cox proportional hazards regression models. Nineteen AVMs exhibited recurrence on follow-up imaging. The recurrence rates after complete obliteration at 6 months, 1 year, and 2 years were 4.35%, 9.78%, and 13.0%, respectively. Multivariate Cox regression analysis identified diffuse nidus (HR 3.208, 95% CI 1.030-9.997, p=0.044) as an independent risk factor for recurrence. Kaplan-Meier analysis confirmed a higher cumulative risk of recurrence with diffuse nidus (log-rank, p=0.016). Further, in the exploratory analysis of the effect of embolization timing after AVM rupture on recurrence after the complete obliteration, embolization within 7 days of the hemorrhage was found as an independent risk factor (HR 4.797, 95% CI 1.379-16.689, p=0.014). Kaplan-Meier analysis confirmed that embolization within 7 days of the hemorrhage was associated with a higher cumulative risk of recurrence in ruptured AVMs (log-rank, p<0.0001). This study highlights the significance of diffuse nidus as an independent risk factor for recurrence after complete embolization of AVMs. In addition, we identified a potential recurrent risk associated with early embolization in ruptured AVMs.

Re-rupture in ruptured brain arteriovenous malformations: a retrospective cohort study based on a nationwide multicenter prospective registry

BACKGROUND

This study aimed to investigate the natural history of re-rupture in ruptured brain arteriovenous malformations (AVMs) and to provide comprehensive insights into its associated factors and prevention.

METHODS

This study included 1712 eligible ruptured AVMs from a nationwide multicenter prospective collaboration registry between August 2011 and September 2021. The natural rupture risk before intervention and the annual rupture risk after intervention were both assessed. Cox proportional hazard regression models and Kaplan-Meier survival curves were used to explore independent factors associated with AVM re-rupture. The correlation between these factors and AVM re-rupture was verified in multiple independent cohorts, and the prevention effect of intervention timing and intervention strategies on AVM re-rupture was further analyzed.

RESULTS

The annual re-rupture risk in ruptured AVMs was 7.6%, and the cumulative re-rupture risk in the first 1, 3, 5, and 10 years following the initial rupture were 10%, 25%, 37.5%, and 50%, respectively. Cox proportional hazard regression analysis confirmed adult patients, ventricular system involvement, and any deep venous drainage as independent factors associated with AVM re-rupture. The intervention was found to significantly reduce the risk of AVM re-rupture (annual rupture risk 11.34% vs 1.70%, p<0.001), especially in those who underwent surgical resection (annual rupture risk 0.13%).

CONCLUSIONS

The risk of re-rupture in ruptured AVMs is high. Adult patients, ventricular system involvement, and any deep venous drainage are independent risk factors for re-rupture. Applying the results universally to all ruptured AVM cases may be biased. Intervention could effectively reduce the risk of re-rupture.

Comparison of Long-Term Outcomes in Ruptured Diffuse Brain Arteriovenous Malformations Between Interventional Therapy and Conservative Management

Brain arteriovenous malformations (AVMs) with a diffuse nidus structure present a therapeutic challenge due to their complexity and elevated risk of hemorrhagic events. This study examines the long-term effectiveness of interventional therapy versus conservative management in reducing hemorrhagic stroke or death in patients with ruptured diffuse AVMs. The analysis was conducted based on a multi-institutional database in China. Patients were divided into two groups: conservative management and interventional therapy. Using propensity score matching, patients were compared for the primary outcome of hemorrhagic stroke or death and the secondary outcomes of disability and neurofunctional decline. Out of 4286 consecutive AVMs in the registry, 901 patients were eligible. After matching, 70 pairs of patients remained with a median follow-up of 4.0 years. The conservative management group showed a trend toward higher rates of the primary outcome compared to the interventional group (4.15 vs. 1.87 per 100 patient-years, P = 0.090). While not statistically significant, intervention reduced the risk of hemorrhagic stroke or death by 55% (HR, 0.45 [95% CI 0.18-1.14], P = 0.094). No significant differences were observed in secondary outcomes of disability (OR, 0.89 [95% CI 0.35-2.26], P = 0.813) and neurofunctional decline (OR, 0.65 [95% CI 0.26 -1.63], P = 0.355). Subgroup analysis revealed particular benefits in interventional therapy for AVMs with a supplemented S-M grade of II-VI (HR, 0.10 [95% CI 0.01-0.79], P = 0.029). This study suggests a trend toward lower long-term hemorrhagic risks with intervention when compared to conservative management in ruptured diffuse AVMs, especially within supplemented S-M grade II-VI subgroups. No evidence indicated that interventional approaches worsen neurofunctional outcomes.

Association of nidus size and rupture in brain arteriovenous malformations: Insight from angioarchitecture and hemodynamics

This study aims to investigate the correlation between AVM size and rupture by examining natural history, angioarchitecture characteristics, and quantitative hemodynamics. A retrospective review of 90 consecutive AVMs from the MATCH registry was conducted. Patients were categorized into small nidus (< 3 cm) and large nidus (≥ 3 cm) groups based on the Spetzler-Martin grading system. Natural history analysis used prospective cohort survival data, while imaging analysis examined angioarchitecture characteristics and quantitative hemodynamic parameters measured with QDSA. The small-nidus group had a significantly higher annualized rupture risk (2.3% vs. 1.0%; p = 0.011). Cross-sectional imaging revealed independent hemorrhagic risk factors, including small nidus (OR, 4.801; 95%CI, 1.280-18.008; p = 0.020) and draining vein stenosis (OR, 6.773; 95%CI, 1.179-38.911; p = 0.032). Hemodynamic analysis identified higher stasis index in the feeding artery (OR, 2.442; 95%CI, 1.074-5.550; p = 0.033), higher stasis index in the draining vein (OR, 11.812; 95%CI, 1.907-73.170; p = 0.008), and lower outflow gradient in the draining vein (OR, 1.658; 95%CI, 1.068-2.574; p = 0.024) as independent predictors of AVM rupture. The small nidus group also showed a higher likelihood of being associated with hemorrhagic risk factors. Small AVM nidus has a higher risk of rupture based on natural history, angioarchitecture, and hemodynamics. Clinical Trial Registration-URL: http://www.clinicaltrials.gov . Unique identifier: NCT04572568.