Rupture Of Arteriovenous Malformation Research Articles

Hypothesizing the interplay of thrombus formation, wall enhancement, and perifocal edema as predictive factors for rupture in brain AVMs

The presence of shear stress within intracranial AVMs (arteriovenous malformations) due to high flow, perinidal angiogenesis, intranidal aneurysms, and biological factors are presumed risk factors for rupture. However, emerging imaging and histological evidence suggests that risk factors for AVM rupture may extend beyond the classical understanding. The presence of perifocal edema at the time of rupture, luminal thrombosis, and vessel wall enhancement on vessel wall MRI elucidate the possibility of an underlying inflammatory process within AVMs, which may predispose them to instability and eventual rupture. We hypothesize that for some AVM ruptures, the occurrence of thrombosis within vascular outpouchings of the AVM initiates a cascade of events, including local hypoxia, inflammation, breakdown of the blood–brain barrier and wall matrix degradation, which is evident from the presence of perifocal edema and vessel wall enhancement observed on imaging. These changes might ultimately raise the risk of AVM rupture and subsequent hemorrhage. Understanding this inflammatory component offers promising insights into AVM pathogenesis and may facilitate the development of preventive strategies to mitigate rupture risk.

Rupture risk assessment in cerebral arteriovenous malformations: an ensemble model using hemodynamic and morphological features

BackgroundCerebral arteriovenous malformation (AVM) is a cerebrovascular disorder posing a risk for intracranial hemorrhage. However, there are few reliable quantitative indices to predict hemorrhage risk accurately. This study aimed to...

Ultra-early neurological deterioration following a brain arteriovenous malformation rupture.

This study aims to explore the impact of ultra-early neurological deterioration (U-END) on the outcome (mortality and poor neurological status) following a brain arteriovenous malformation (BAVM) rupture and identify determinants of U-END. Patients with BAVM ruptures admitted to a single tertiary care center were retrospectively reviewed. U-END was defined as a worsening by two or more points on the Glasgow Coma Scale (GCS). U-END was tested as a potential predictor of in-hospital mortality and poor outcomes. Univariate and multivariate analyses were performed to identify determinants of U-END. Patients with U-END were also matched and compared with BAVM rupture controls presenting with a GCS close or equal to either their initial or their lowest GCS. A total of 248 patients with BAVM ruptures met the inclusion criteria, with 39 (15.7%) patients presenting with U-END. U-END was not associated with and was not an independent predictor of in-hospital mortality (12.8 vs. 10.5% in the rest of the study population; p = 0.67) or poor outcomes (39.5 vs. 36.9%; p = 0.77). The only independent determinants of U-END were hydrocephalus (OR 2.6 [95%CI, 1.1-6.4]; p = 0.03) and intraventricular hemorrhage (IVH; OR 3.5 [95%CI, 1.1-11.7]; p = 0.04). When compared to the initial GCS control group, U-END patients more often presented with IVH (89.5 vs. 64.1%; p = 0.009) and hydrocephalus (73 vs. 38.5%; p = 0.003). When compared to the lowest GCS control group, U-END patients had lower early S100B serum levels (0.35 ± 0.37 vs. 0.83 ± 1; p = 0.009) and a lower rate of poor outcome (39.5 vs. 64.9%; p = 0.03). Ultra-early neurological deterioration in ruptured BAVMs did not result in increased mortality or poor outcomes and was most often related to IVH and hydrocephalus.

Early versus Delayed Surgical Management of Ruptured Arteriovenous Brain Malformations in a Tertiary Referral Center in Colombia, South America

IntroductionSurgical timing after rupture of brain arteriovenous malformations (AVMs) is controversial. There is scarce literature on AVM surgical outcomes from developing countries. This study aims to determine if there is a difference between early and delayed surgical resection for patients with ruptured brain AVMs. MethodsThis single-center retrospective review included patients who underwent surgical resection for ruptured brain AVMs in Colombia. Patients were stratified by the timing of surgical intervention relative to the rupture into early (≤72 hours of bleeding) and delayed (>72 hours) resection. Continuous variables were analyzed using an independent t-test, and dichotomous variables were analyzed using a chi-square test. A linear-regression analysis was performed with the final mRankin score at 2 years as the dependent variable; p<0.05 was considered significant. ResultsThirty-one patients were identified. The early treatment group included 14(45.2%) patients, and the delayed group, 17(54.8%) patients. The mean(SD) length of time between AVM rupture and surgical resection was 1.6±1.2 days and 12.4±8.4 days, respectively(p<0.001). There were no differences regarding demographics, perioperative variables and postoperative outcomes between groups. In the linear-regression analysis, the only variable that had a significant association with the final mRankin score was the initial GCS, which had a β coefficient of -0.6341(95%CI-0.41,-0.017,p=0.035) ConclusionIn this case series of 31 patients from a developing country, there were no differences in clinical outcomes at the final follow-up between acute and delayed surgical interventions for ruptured AVMs. The most important factor associated with the final outcomes was the initial GCS.

Timing of Embolization, Radiosurgery, and Resection of Arteriovenous Malformations in Pediatric Patients: A Retrospective, Descriptive Study

ObjectiveCerebral arteriovenous malformations (AVMs) are a challenging pathology in pediatric patients, carrying a high risk of morbidity and mortality. Treatment modalities include resection, endovascular embolization and stereotactic radiosurgery (SRS). There is currently no consensus favoring one modality over another. Timing of multimodal therapy with embolization/SRS and resection is not well explored in the literature. Here we present a series of pediatric AVM patients, with special attention paid to the timing of treatment. MethodsElectronic medical records of all pediatric patients (<18 years at treatment) with AVMs treated at our institution were retrospectively reviewed after IRB approval. Demographic information, AVM characteristics, treatment variables and outcomes were recorded. Results27 total patients were included. 21 (77.8%) presented with a ruptured AVM. 6 patients (28.6%) had an GCS of 3 to 10, and underwent treatment within 24 hours of presentation. 10 patients (47.6 %) with a GCS of 12 to 15 were treated between 24 to 120 hours. 5 patients (23.8%) were treated 3 weeks to 14 months after AVM rupture. 96% of our cohort, regardless of rupture status, had mRS of 1-2 at most recent follow-up. ConclusionsWe present our institution’s experience with pediatric AVM’s, focusing on the timing of treatment. Based on our experience, early treatment of AVMs seems to be safe and effective regardless of rupture status.

Intraventricular hemorrhage secondary to ruptured arteriovenous malformation: A case report

Introduction: An arteriovenous malformation (AVM) is a lesion in which the feeding artery and the draining vein are connected by a coiled, tortuous vascular link. This nidus is where arteriovenous shunting occurs. While pediatric AVM is uncommon, there has been evidence of possible impairments and an increased risk of hemorrhage. This study aimed to elaborate on a rare case of pediatric arteriovenous malformation with intraventricular hemorrhage. Case report: A male patient, fifteen years of age, was referred from P hospital due to a severe headache that was accompanied by nausea and vomiting two days prior to hospital admission. Chief Computed Tomography Digitizing and Angiographic Images In the left lateral ventricle, the posterior horn of the right lateral ventricle, the third ventricle, and the left pericallosal area AVM (Spletzer Martin grading: 2), intraventricular hemorrhage (IVH), and moderate cerebral edema were all seen during an angiography. AVM was managed conservatively with head positioning 30o, analgesics, and ranitidine. Phenytoin was given as a precaution for seizure in intracerebral hemorrhage. The headache improved gradually during the hospital stay. Upon follow-up at the outpatient clinic, headache and other neurological symptoms were absent, and the patient had typical vital signs. Conclusion: AVM rupture can cause IVH that occurs more often in young patients. Management of pediatric AVM requires discussion among pediatric neurologists, neurosurgeons, and interventional radiologists to decide the best care for the patient. AVM patients who received conservative treatment had a higher risk of bleeding and, therefore, required routine monitoring.

Intracranial Arteriovenous Malformations During Pregnancy and Puerperium-A Retrospective Nationwide Population-Based Cohort Study.

The knowledge about the management of patients with brain arteriovenous malformations (AVM) during pregnancy is limited, owing partly to insufficient evidence about the outcomes of newborns. This study aims to explore symptomatic AVMs and their outcomes during pregnancy, delivery, and the postpartum period. We conducted a retrospective analysis by combining patients with symptomatic AVM from a nationwide population-based cohort of all women with a pregnancy resulting in delivery during 1987 to 2016 (n = 1 773 728 deliveries) and our AVM database (n = 805, 1942-2014). Cerebrovascular events during pregnancy were identified through International Classification of Diseases-9, International Classification of Diseases-10, or surgical procedure codes from the Hospital Discharge and Medical Birth Registers. Our analysis focused on treatment characteristics and outcomes of patients with AVM hemorrhage or symptomatic AVM during pregnancy, delivery, or puerperium. A total of 28 women with symptomatic AVMs during pregnancy, delivery, or postpartum period were followed for an average of 12.8 years (SD = 15.5) after admission. Among them, 21 (75%) experienced AVM hemorrhages during pregnancy, puerperium, or delivery. The mean age of patients was 28.9 years (SD = 5.5). Hemorrhages occurred predominantly during the second (n = 9, 43% of all ruptures) or the third trimester (n = 5, 24%). Two AVM ruptures occurred during labor. Treatment for AVM took place during pregnancy (n = 7, 25%) or puerperium (n = 3, 14%) in 10 patients (35.7%). Only 5 mothers (17.8%) had not been previously pregnant. There was no significant difference in mean Apgar scores between those with AVM hemorrhage (8.3) and those without (8.4). Most mothers in the study had prior pregnancies, suggesting a potentially weaker association between AVM rupture and pregnancy compared to previous reports. Notably, 2 AVM ruptures occurred during spontaneous vaginal deliveries. Outcomes were generally favorable in both mothers and infants. More research is needed to refine our understanding of the optimal timing for invasive treatment during pregnancy.

Adenosine-assisted embolization of cerebral arteriovenous malformations: a systematic review and meta-analysis

BackgroundCerebral arteriovenous malformations (AVMs) are complex lesions that can cause hemorrhagic stroke and significant neurological disability. Adenosine induces cardiac standstill and hypotension, which are thought to be useful during cerebral...

Three-Pillar Expansive Craniotomy in Children with Acute Ruptured Supratentorial Brain Arteriovenous Malformations

Acute rupture and hemorrhage of pediatric brain arteriovenous malformations (AVMs) may lead to cerebral herniation or intractable intracranial hypertension, necessitating emerging surgical interventions to alleviate intracranial pressure. However, there is still controversy regarding the timing of treatment for ruptured AVMs. This study aimed to assess the feasibility of utilizing three-pillar expansive craniotomy (3PEC) at different times during the treatment of pediatric ruptured supratentorial AVMs. A retrospective analysis was conducted on all consecutive cases of acute rupture in supratentorial AVM children who underwent 3PEC at a single institution from 2020 to 2022. General information, clinical characteristics, radiological data, and prognosis were reviewed and analyzed. Thirteen children were included in the analysis. The intracranial pressure of all patients decreased to below 15mmHg within 10days. The expansion volume of the cranial cavity of the patients increased by 18.3cm3 (95% confidence interval, 10.2-26.3; P<0.001) compared to the hematoma volume. None of the patients required decompressive craniectomy due to intractable intracranial hypertension caused by cerebral swelling. The median waiting period for patients with delayed AVMs treatment was 8days, during which no rebleeding occurred. Emergency intervention with 3PEC in children experiencing acutely ruptured supratentorial AVMs appears to be feasible. For children requiring delayed management of the AVMs, 3PEC may diminish the risk of rebleeding during the waiting period and shorten the waiting period.

Thoracic spinal cord injury after surgical removal of a ruptured cerebellar arteriovenous malformation in a patient in the Concorde position: illustrative case.

Thoracic spinal cord injury after posterior cranial fossa surgery in younger patients is a rare complication. There have been reports of this complication in tumor and spine fields but not in vascular surgery. A 22-year-old-man experienced cerebellar arteriovenous malformation rupture, and the malformation was surgically removed with the man in the Concorde position. After surgery, the man had severe paraplegia, and a thoracic spinal cord injury was diagnosed. In younger patients, cervical hyperflexion in the Concorde position can cause thoracic spinal cord injury even in surgery for cerebrovascular disease.

311 Rupture-Risk Stratifying Patients With Cerebral Arteriovenous Malformations Using Quantitative Hemodynamic Flow Measurements

INTRODUCTION: Up to 60% of cerebral arteriovenous malformations (AVMs) present with an intracranial hemorrhage, however, noninvasive neuroimaging has increasingly diagnosed incidental AVMs. AVM management depends on weighing the lifetime rupture risk against the risks of intervention. Although AVM rupture risk relies primarily on angioarchitectural features, measuring hemodynamic flow is gaining traction. An accurate understanding of AVM hemodynamic flow parameters will help stratify patients by rupture risk and select treatment plans. METHODS: The literature was reviewed for articles that quantified AVM flow. RESULTS: Quantitative digital subtraction angiography (QDSA), 4D spin-labeled magnetic resonance angiography (4D-SL-MRA), and 4D-Flow magnetic resonance imaging (4D-Flow-MRI) studies measure relative flow; 3D phase-contrast MRI (PC-MRI) studies measure relative and true flow; and quantitative MRA (QMRA) studies measure true flow. QDSA studies have correlated increased rupture risk with prolonged venous outflow, however there are mixed findings with respect to arterial inflow. Similarly, a higher AVM inflow-to-outflow ratio has been associated with greater rupture risk in studies using PC-MRI. 4D-SL-MRA studies, on the other hand, have demonstrated a lower time-to-peak draining-vein-to-feeder-artery ratio in patients with AVM rupture. Finally, 4D-Flow-MRI studies have shown inconsistent findings whereas QMRA studies have found no significant associations between AVM hemodynamic flow parameters and rupture risk. CONCLUSIONS: Quantitative hemodynamic studies on the relationship between AVM flow and rupture risk have not reached a clear consensus; however, the preponderance of data suggests that higher arterial inflow and lower venous outflow in the AVM nidus contribute to increased hemorrhagic risk. Future studies should consider using larger sample sizes and standardized definitions of hemodynamic parameters to reach a consensus. In the meantime, classic angioarchitectural features may be more strongly correlated with AVM rupture than the amount of blood flow.

313 Development and Validation of a Scoring System for Hemorrhage Risk in Brain Arteriovenous Malformations

INTRODUCTION: The dilemma between natural rupture risk and adverse outcomes of intervention is of major concern for patients with unruptured arteriovenous malformations (AVMs). The existing risk score for AVM rupture includes factors that are controversial and lacks prospective validation. METHODS: This prognostic study developed a prediction model derived from a single-center cohort (derivation cohort) and validated in a multicenter external validation cohort and a conservative treatment validation cohort. Patients were recruited from a nationwide multicenter prospective collaboration registry in China. A total of 4135 patients were enrolled. 3962 patients were included (3585 in the derivation cohort and 377 in the multicenter external validation cohort); 1028 patients from the derivation cohort who had time-to-event data and prerupture imaging results were included in the conservative treatment validation cohort. RESULTS: Four risk factors were used to develop the scoring system: ventricular system involvement, venous aneurysm, deep location, and exclusively deep drainage (VALE). The VALE scoring system performed well in all 3 cohorts, with areas under the receiver operating characteristic curve of 0.77 (95% CI, 0.75-0.78) in the derivation cohort, 0.85 (95% CI, 0.81-0.89) in the multicenter external validation cohort, and 0.73 (95% CI, 0.65-0.81) in the conservative treatment validation cohort. The 10-year hemorrhage-free rate was 95.5% (95% CI, 87.1%-100%) in the low-risk group, 92.8% (95% CI, 88.8%-97.0%) in the moderate-risk group, and 75.8% (95% CI, 65.1%-88.3%) in the high-risk group; the model discrimination was significant when comparing these rates between the high-risk group and the low- and moderate-risk groups (p &lt; .001 for both comparisons). CONCLUSIONS: In this prognostic study, the VALE scoring system was developed to distinguish rupture risk among patients with AVMs. The stratification of unruptured AVMs may enable patients with low risk of rupture to avoid unnecessary interventions.

Overloaded transnidal pressure gradient as the hemodynamic mechanism leading to arteriovenous malformation rupture: a quantitative analysis using intravascular pressure monitoring and color-coded digital subtraction angiography

BackgroundThe hemodynamics of brain arteriovenous malformations (AVMs) may have implications for hemorrhage. This study aimed to explore the hemodynamics of ruptured AVMs by direct microcatheter intravascular pressure monitoring (MIPM) and...

Microsurgical resection of a ruptured intraventricular arteriovenous malformation in a neonate: considerations in management. Illustrative case.

Arteriovenous malformations (AVMs) are the most common cause of intracranial hemorrhage in children, although they are rarer in neonates. Age, location, lesion architecture, and rupture status define treatment options. Sparse literature exists to guide the management of clinically symptomatic intraventricular AVM rupture in neonates. We highlight the case of a neonate with a ruptured intraventricular AVM to showcase considerations in treatment, discuss surgical technique, and help guide management. An 18-day-old female presented with lethargy in extremis and was found to have new intraventricular hemorrhage. Angiogram revealed a Spetzler-Martin grade 2 AVM with a right posterior choroidal feeder and deep venous drainage within the ventricle. Her age limited radiosurgical and endovascular interventions. She underwent an interhemispheric, transcollosal, intraventricular approach for complete AVM resection. Perioperative care was managed by a multidisciplinary team, successfully mitigating the patient's high risk of hemovascular collapse. Stereotactic radiosurgery, endovascular embolization, and microsurgery are options for AVM obliteration, and multimodal therapy must be tailored to the lesion and patient. Conservative management can also be considered. Each intervention carries risks and varying likelihoods of success. Balancing these outcomes is challenging without definitive, high-quality, evidence-based guidance. The best treatment maximizes the chance of AVM obliteration while minimizing morbidity.

Machine Learning Models for Brain Arteriovenous Malformations Presenting with Hemorrhage Based on Clinical and Angioarchitectural Characteristics

This study aims to develop the best diagnostic model for brain arteriovenous malformations (bAVMs) rupture by using machine learning (ML) algorithms. We retrospectively included 353 adult patients with ruptured and unruptured bAVMs. The clinical and radiological data on patients werecollected. The significant variables were selected using univariable logistic regression. We constructed and compared the predictive models using five supervised ML algorithms, multivariable logistic regression, and R2eDAVM scoring system. A complementary systematic review and meta-analysis of studies was aggregated to explore the potential predictors for bAVMs rupture. We found that a small nidus size of <3cm, deep and infratentorial location, longer filling time, and deep and single venous drainage were associated with a higher risk of bAVMs rupture. The multilayer perceptronmodel showed the best performance with an area under the curvevalue of 0.736 (95% CI 0.67-0.801) and 0.713 (95% CI 0.647-0.779) in the training and test dataset, respectively. In our pooled analysis, we also found that the male sex, a single feeding artery, hypertension, non-White race, low Spetzler-Martin grade, and coexisting aneurysms are risk factors for bAVMs rupture. This study further demonstrated the clinical and angioarchitectural characteristics in predicting bAVMs hemorrhage.

Recurrence of pediatric cerebral arteriovenous malformation after obliteration by radiosurgery: a case report

The rupture of a cerebral arteriovenous malformation is the most common cause of cerebral hemorrhage in children, with recurrence rates reported to be higher than that in adults. Herein, we present the case of a 4-year-old child who initially demonstrated obliteration of a ruptured brain arteriovenous malformation after initial Gamma Knife radiosurgery, but subsequently experienced delayed recurrence, ultimately necessitating a second Gamma Knife radiosurgery procedure. By reviewing this case, we aim to explore considerations regarding the recurrence, treatment, and follow-up strategies for pediatric arteriovenous malformations.

Early Treatment of Ruptured Cerebral Arteriovenous Malformations: Analysis of Neurological Outcomes and Health Care Costs.

The timing of surgical resection is controversial when managing ruptured arteriovenous malformations (AVMs) and varies considerably among centers. To retrospectively analyze clinical outcomes and hospital costs associated with delayed treatment in a ruptured cerebral AVM patient cohort. Patients undergoing surgical treatment for a ruptured cerebral AVM (January 1, 2015-December 31, 2020) were retrospectively analyzed. Patients who underwent emergent treatment of a ruptured AVM because of acute herniation were excluded, as were those treated >180 days after rupture. Patients were stratified by the timing of surgical intervention relative to AVM rupture into early (postbleed days 1-20) and delayed (postbleed days 21-180) treatment cohorts. Eighty-seven patients were identified. The early treatment cohort comprised 75 (86%) patients. The mean (SD) length of time between AVM rupture and surgical resection was 5 (5) days in the early cohort and 73 (60) days in the delayed cohort ( P < .001). The cohorts did not differ with respect to patient demographics, AVM size, Spetzler-Martin grade, frequency of preoperative embolization, or severity of clinical presentation ( P ≥ .15). Follow-up neurological status was equivalent between the cohorts ( P = .65). The associated mean health care costs were higher in the delayed treatment cohort ($241 597 [$99 363]) than in the early treatment cohort ($133 989 [$110 947]) ( P = .02). After adjustment for length of stay, each day of delayed treatment increased cost by a mean of $2465 (95% CI = $967-$3964, P = .002). Early treatment of ruptured AVMs was associated with significantly lower health care costs than delayed treatment, but surgical and neurological outcomes were equivalent.

Impact of COVID-19 pandemic on treatment and outcomes of cerebral arteriovenous malformations

BackgroundThere has been a recent decrease in interventional management of cerebral arteriovenous malformations (AVMs). The objective of our study was to evaluate the changing patterns in management of AVMs in...

Neuraxial Anesthesia for Cesarean Section in Pregnant Women with Ruptured Arteriovenous Malformation

Background: Maternal stroke as a result of ruptured arteriovenous malformation (AVM) in pregnancy is rare. However, AVM rupture can result in high morbidity during pregnancy and the puerperium. In its management, several special considerations are needed to ensure the welfare of the mother and fetus. This article will discuss anesthesia in pregnant patients after hemorrhagic stroke due to AVM rupture under neuraxial anesthesia.&#x0D; Case presentation: A 25-year-old patient with a second pregnancy with twins at 33 weeks came with complaints of water coming out of the birth canal 1.5 hours before admission to the hospital. The patient was diagnosed with G2P0010 33 Weeks 3 days Gemelli H/H head presentation, buttocks presentation, intracerebral hemorrhage (ICH) et cause suspected AVM rupture, premature rupture of membranes, and first-day febrile observation and planned to undergo cito cesarean section.&#x0D; Conclusion: Neuraxial anesthesia is one of the safe options for pregnant patients after a hemorrhagic stroke with controlled intracranial pressure.

Factors Associated with Unfavorable Clinical Presentations in Patients with Ruptured BrainArteriovenous Malformations

Rupture of brain arteriovenous malformations (bAVMs) carries potentially devastating consequences. For patients presenting with ruptured bAVMs, several clinical grading systems have been shown to predict long-term patient morbidity and may be taken into consideration when making clinical decisions. Unfortunately, use of these scoring systems is typically limited to their prognostic value and offer little to patients in therapeutic benefit. Tools are needed not only to predict prognosis for patients experiencing ruptured bAVMs but to gain insight into what characteristics predispose patients to poor long-term outcomes before they rupture. Our objective was to find clinical, morphologic, and demographic variables that correlate with unfavorable clinical grades on presentation in patients with ruptured bAVMs. We retrospectively reviewed a cohort of patients with ruptured bAVMs. Linear regression models were used to test whether Glasgow Coma Scale (GCS) and Hunt-Hess scores on presentation(outcomes) were associated with patient and arteriovenous malformation (AVM) characteristics (predictors) individually. GCS and Hunt-Hess were assessed following bAVM rupture for 121 brain cases. The median age at rupture was 28.5 years, and 62 (51%) were female. Smoking history was associated with worse GCS; current and past smokers had GCS scores 1.33 points lower on average than nonsmokers (95% confidence interval [CI] -2.59 to -0.07, P= 0.039) and had worse Hunt-Hess scores (0.42, 95% CI 0.07-0.77, P= 0.019). Associated aneurysms were associated with worse GCS (-1.60, 95% CI -3.16 to -0.05, P= 0.043) and trended towards worse Hunt-Hess scores (0.42 points, 95% CI -0.01 to 0.86, P= 0.057). Patient smoking status and presence of an AVM associated aneurysm were shown to have modest correlations with unfavorable clinical grades (Hunt-Hess, GCS) on presentation, with unfavorable clinical grades being associated with long-term patient prognosis following bAVM rupture. Further investigation using AVM-specific grading scales and external data are needed to determine the utility of these and other variables in clinical practice for patients with bAVM.