Aortic Steal Correlates with Acute Organ Dysfunction and Short-Term Outcomes in Neonates with Vein of Galen Malformation.

INTRODUCTION: Vein of Galen aneurysmal malformation (VGAM) is a rare, congenital cerebrovascular malformation with high morbidity and mortality. Parameters to foresee clinical progression and allow individualized parent counseling are lacking. The aim of this study was to evaluate aortic steal measured by Doppler ultrasound as a prognostic parameter in these neonates. METHODS: A retrospective monocentric analysis of cardiac ultrasound exams before embolization in neonates with VGAM was conducted. Percentage of aortic steal measured by time-averaged maximum velocity above and below the zero flow baseline by pulsed Doppler ultrasound at the preductal aortic isthmus was calculated. Association of aortic steal with parameters of acute organ dysfunction (Bicêtre neonatal evaluation score [BNES], neonatal multiple organ dysfunction score [NeoMODS]) and mortality and determination of correlation between aortic steal and cerebral damage on initial and follow-up cerebral magnetic resonance imaging (cMRI) were evaluated. RESULTS: Twelve neonates were included, of which 3 died. Per 10 percentage point increase of aortic steal, BNES decreased by 1.64 (95% confidence interval [CI]: 1.28-2.0) points and the maximum observed NeoMODS increased by 1.25 (CI: 0.94-1.57) points. The odds for mortality increased by 2.3 (CI: 1.14-13.67) per 10 percentage point increase of aortic steal. There was a correlation between aortic steal and cerebral damage at baseline (white matter ρ [rho] = 0.34, gray matter ρ = 0.81) and follow-up (white matter ρ = 0.80, gray matter ρ = 0.72). CONCLUSION: The degree of aortic steal in neonates with VGAM was highly associated with the severity of organ dysfunction, disease progression on cMRI, and mortality.

Direct Transverse Sinus Puncture for Transvenous Coil Embolization of Vein of Galen Malformations: Innovating Existing Techniques.

BACKGROUND AND IMPORTANCE: Vein of Galen malformations (VOGMs) are complex arteriovenous malformations in neonates and young children. Recent advances in endovascular interventions have drastically improved treatment and clinical outcomes in what was previously high-morbidity, high-mortality disease. The high-flow shunt pathophysiology in VOGMs can lead to dynamic changes in the malformation angioarchitecture, and over time patients can develop jugular bulb stenosis. In the setting of inaccessible transvenous access to the malformation for endovascular embolization in cases where transarterial embolization is inadequate, a combined surgical and endovascular technique must be used. We present the first successful modern-day application of direct puncture through transverse sinus for transvenous embolization of a VOGM. CLINICAL PRESENTATION: We present 2 unique cases of complex VOGM malformations in patients who had previously undergone staged endovascular embolization for reduction of flow within the malformation. On follow-up, in both cases, there was development of severe sigmoid sinus and jugular bulb stenosis, increasing intracranial venous congestion and causing marked clinical deterioration. The stenosis prevented traditional transvenous access and treatment. We describe a direct puncture transverse sinus access using a burr hole approach for endovascular transvenous embolization in both cases with successful clinical outcomes. CONCLUSION: Direct access using burr hole craniotomy to the transverse sinus for transvenous endovascular embolization is a safe approach in the setting of severe jugular bulb stenosis for treatment of VOGMs. This technique can be done efficiently to achieve complete flow elimination in the malformation, in cases where that is called for, without significant risks or complications related to the approach.

Pulmonary Hypertension in Infants and Children with Vein of Galen Malformation and Association with Clinical Outcomes.

OBJECTIVE: To assess the extent and resolution of pulmonary hypertension (PH), cardiovascular factors, and echocardiographic findings associated with mortality in infants and children with vein of Galen malformation (VOGM). STUDY DESIGN: We performed a retrospective review of 49 consecutive children with VOGM admitted to Boston Children's Hospital from 2007 to 2020. Patient characteristics, echocardiographic data, and hospital course were analyzed for 2 cohorts based on age at presentation to Boston Children's Hospital: group 1 (age ≤60 days) or group 2 (age >60 days). RESULTS: Overall hospital survival was 35 of 49 (71.4%); 13 of 26 (50%) in group 1 and 22 of 23 (96%) in group 2 (P < .001). High-output PH (P = .01), cardiomegaly (P = .011), intubation (P = .019), and dopamine use (P = .01) were significantly more common in group 1 than group 2. Among patients in group 1, congestive heart failure (P = .015), intubation (P < .001), use of inhaled nitric oxide (P = .015) or prostaglandin E1 (P = .030), suprasystemic PH (P = .003), and right-sided dilation were significantly associated with mortality; in contrast, left ventricular volume and function, structural congenital heart disease, and supraventricular tachycardia were not associated. Inhaled nitric oxide achieved no clinical benefit in 9 of 11 treated patients. Resolution of PH was associated with overall survival (P < .001). CONCLUSIONS: VOGM remains associated with substantial mortality among infants presenting at ≤60 days of life owing to factors associated with high output PH. Resolution of PH is an indicator associated with survival and a surrogate end point for benchmarking outcomes.

Vein of Galen Malformations in adults.

OBJECTIVE: Vein of Galen Malformations (VoGM) are rare vascular malformations, typically seen in pediatric age groups. Even more rarely, VoGM's may be seen later in adulthood. In this case report and systematic review, we provide a thorough description of the current literature as well as provide a case example exploring the diagnosis, imaging, treatment, and management of VoGM in adults. METHODS: In accordance with PRISMA guidelines, we performed a systematic literature search for all relevant cases and case series of VoGM in adult patients. The reference list of all articles were reviewed for additional relevant cases. Articles were included if they described a VoGM of a patient over the age of 18 years old and published in English. 149 articles were originally identified and 26 described cases met our inclusion criteria. RESULTS: In our literature review we found 26 patients that met our inclusion criteria. We found 14 male patients and 12 female patients. The mean age at presentation was 37.2 years (median=34 years, SD= 13.6 years). The most common presenting symptoms of patient were headache (n = 9), seizure (n = 6), and vomiting (n = 4). Of the 12 cases which clearly reported the subtype of VoGM, the choroidal type was more frequently seen (n = 10) compared to the mural type (n = 2). In 3 patients, the VoGM was thrombosed at time of diagnosis. Of the 26 patients, endovascular treatment was performed most frequently (n = 8) but some received microsurgical treatment (n = 4) or were treated conservatively (n = 6). Other treatment modalities included (ventriculoperitoneal shunt, ventriculostomy) (n = 5). In 3 cases treatment was not specified. In comparison to VoGM seen in pediatric or neonatal populations, VoGM in adults generally resulted in more favorable outcomes with only 2 patients reported to have passed away following treatment. CONCLUSION: VoGM remains a rare finding amongst the adult population. Hence, we described the clinical presentation, treatment modalities, and outcomes of the cases described in the English literature. Perhaps due to the rate of thrombosis and the unique angioarchitecture seen in adult VoGM patients, outcomes were generally more favorable than those described in the literature in pediatric or neonate VoGM patients.

Overcoming roadblocks in clinical innovation via high fidelity simulation: use of a phantom simulator to achieve FDA and IRB approval of a clinical trial of fetal embolization of vein of Galen malformations.

BACKGROUND: Vein of Galen malformation (VOGM) is a rare, life-threatening vascular malformation in neonates and is treated with embolization. However, even at the most experienced centers, patients face high mortality and morbidity. In utero treatment options have been limited by lack of animal models or simulations. OBJECTIVE: To create a novel ultrasound phantom simulator for a preclinical feasibility study of in utero fetal intervention for VOGM. METHODS: Novel phantoms were designed and built in two configurations of spherical and windsock shape from cryogel material to mimic the salient vasculature of the fetal VOGM, based on real-patient fetal MR imaging dimensions. Critical anatomy was realistically mimicked within this model and transtorcular ultrasound-guided coil deployment was simulated. Each phantom model was assessed before and after treatment to evaluate coil mass deposition within the target. RESULTS: The two phantoms underwent pretreatment T2-weighted MR imaging assessment, ultrasound-guided embolization, post-treatment MR and fluoroscopic imaging, and visual inspection of the sliced phantoms for target embolization verification. Postoperative MR scans confirmed realistic compact deposition of the coil masses within the central cavity. Phantom embolization results were submitted as part of the institutional review board and US Food and Drug Administration investigative device exemption approval for a first-in-humans clinical trial of fetal intervention for VOGM. CONCLUSIONS: A phantom simulator for fetal intervention of VOGM produces lifelike results during trial interventions, removing obstacles to feasibility and safety evaluations, typically precluded by non-availability of appropriate animal models. The study provides a proof of concept for potentially wider applications of medical simulation to enable novel procedural advancements in neurointerventions.

Rapid Ventricular Pacing Facilitates Transarterial Embolization in Vein of Galen Malformations.

Background: Mural type vein of Galen malformation (mVOGM) is a congenital high flow arteriovenous shunt between choroidal arteries and the prosencephalic vein of Markowski leading to heart failure and hydrovenous disorder in children. Embolizing fistulous connections can be challenging and typically requires adjunctive techniques such as induced hypotension, balloon-assisted flow control, and creation of a coil basket. These maneuvers add time, complexity, and unpredictability. Rapid ventricular pacing (RVP) has been proposed as an alternative strategy with fewer drawbacks, but has not been well studied. The approach involves catheterizing the right ventricle with a pacing catheter connected to a temporary external pacemaker. Prior to embolization, RVP is initiated to lower cardiac output. Following embolization, pacing is discontinued, and the heart returns to sinus rhythm. Methods: We performed RVP in five mVOGM patients from 4/2020 through 7/2021. Accounting for multiple procedures, RVP was utilized in ten cases and twenty-six pedicles. Results: Ventricular capture was achieved in all instances and was well tolerated, without arrhythmia. Casting the arterial pedicle with liquid embolic immediately adjacent to, or traversing, the fistulous point was achieved in 9/10 cases. There were no procedural complications. In 1 case, creation of a coil basket in the venous pouch was required to achieve a stable arterial cast Conclusions: This report describes the largest case series utilizing RVP in mVOGM. The technique appears safe and well tolerated.

Vein of Galen aneurysmal malformation: rationalizing medical management of neonatal heart failure.

Neonates who present in high output heart failure secondary to vein of Galen aneurysmal malformation can be difficult to manage medically due to the complex physiology that results from the large shunt through the malformation. Though the cardiac function is often normal, right ventricular dilation, severe pulmonary hypertension, and systemic steal can result in inadequate organ perfusion and shock. This report recommends medical management for stabilization of neonates prior to definitive management with endovascular embolization. IMPACT: Vein of Galen aneurysmal malformation (VGAM) is a rare intracranial arteriovenous malformation, which can present in the neonatal period with high output heart failure. Heart failure secondary to VGAM is often difficult to manage and is associated with high mortality and morbidity. Despite optimal medical management, many patients require urgent endovascular embolization for stabilization of their heart failure. This report offers discrete recommendations that can be used by clinicians as guidelines for the medical management of heart failure in newborns with VGAM.

Evolution of transvenous embolization in vein of Galen malformation: case series and review of the literature.

BACKGROUND: Treatment of vein of Galen malformations (VOGMs) has improved greatly since the inception of endovascular treatment. Transvenous embolization (TVE) is an attractive option to achieve complete obliteration. OBJECTIVE: To review the literature on TVE of VOGM and then analyze our practice's unique experience and evolving treatment strategies over 30 years. METHODS: A retrospective review of our clinical database for patients with the diagnosis of VOGM treated between January 2004 and August 2021 was performed. A literature review of 49 relevant articles was also carried out. RESULTS: TVE in VOGM has evolved with initial introduction as a transtorcular (TT) approach, which then lost favor to transarterial embolization (TAE). TAE has been considered the more favorable approach in most high-volume centers. In more recent times, the transvenous embolization (TVE) approach has been revisited as a last treatment to achieve a cure after a series of TAE treatments. We presently favor beginning treatment with staged TAE to reduce flow to the lesion and, importantly, shrink the draining vein. This then allows for the performance of TVE with the Chapot pressure cooker technique (CPCT) with coils and liquid embolic embolization. CONCLUSIONS: TT TVE itself carries a high degree of risk and is most highly associated with long-term morbidities and mortality. Traditional transfemoral/transjugular TVE approaches are safe and effective in simple fistulas with a small venous pouch; however, we believe that the CPCT is the safest technique as a last-stage treatment for its security in avoiding reflux and obtaining occlusion of the small perforators.

The composition of landmark vein of Galen malformation research: the emergence of endovascular treatments.

BACKGROUND: Since the advent of endovascular treatment, the long-term prognosis of vein of Galen malformation (VOGM) has markedly improved; however, the nature of research leading to this point is unclear. The objective of this study was to define the composition of VOGM research to date, by means of a bibliometric analysis of the 100 most cited VOGM articles. METHODS: An electronic search of Elsevier's Scopus database was performed to identify the 100 most cited articles on VOGM screened against predetermined criteria. Data were then compared. RESULTS: The 100 most cited VOGM articles were published between 1974 and 2017 in 38 unique journals and originated from 16 unique countries. Mean citation count and rate were 59.4 citations and 2.9 citations/year, respectively. The USA (n = 42); Hôpital de Bicêtre, France (n = 15); and Dr. Pierre Lasjaunias (n = 16) were the largest individual country, institutional, and author contributors. Compared to the older articles (published < 2000), key differences for newer articles were statistically higher citation rates (P < 0.01), more authors (P < 0.01), higher proportion of endovascular treatment descriptions (P = 0.01), and more originating from Asia Pacific (P < 0.01). CONCLUSIONS: From the 100 most cited VOGM articles to date, there has been a noticeable shift from diagnosing VOGM based on the foundational work by Dr. Lasjaunias to understanding how we can model clinical outcomes now that endovascular treatment has become the standard of care. Significant shifts in prognosis are pending, and the current bibliometric data implicate we are on the precipice of more recent works making an impact in the near future.

Vein of Galen Aneurysmal Malformation with Anomalous Right Superior Vena Cava to the Left Atrium Leading to Atypical Clinical and Echocardiographic Findings.

Vein of Galen aneurysmal malformation (VGAM) is a rare intracranial vascular malformation which typically presents in a critically ill newborn with intractable heart failure, severe pulmonary hypertension, and right heart dilation. We report two unusual cases of neonates with VGAM and anomalous connection of right superior vena cava to the left atrium. Both neonates were diagnosed with VGAM in utero and were clinically stable after birth with dilation of the left atrium and left ventricle and no evidence of pulmonary hypertension. One case with hydrocephalus underwent transcatheter embolization at 1 week of age. The other case without hydrocephalus underwent elective transcatheter embolization at 4 months. We postulate that the presence of a right superior vena cava to the left atrium provides a physiological advantage and counters the left-to-right shunt from the arteriovenous malformation. This provides insight to a potential treatment strategy to improve outcomes in patients with severe heart failure and pulmonary hypertension secondary to VGAM.

Fine, Vascular Network Formation in Patients with Vein of Galen Aneurysmal Malformation.

BACKGROUND AND PURPOSE: A vein of Galen aneurysmal malformation is known to present with recruitment of dural feeders and, in our cohort, a fine, vascular network formation. The vessels we have observed differ from dural vascular recruitment in that they produce a hairlike, collateral network of vessels. We reviewed treatment courses of vein of Galen aneurysmal malformation treatments in a series of 36 cases that displayed a fine, vascular network formation. MATERIALS AND METHODS: We retrospectively analyzed 36 cases of vein of Galen aneurysmal malformation, including tectal/thalamic AVMs, treated at our center from January 2004 to September 2021, and reviewed fine, vascular network formations in the subarachnoid space and subependymal zone alongside the vein of Galen aneurysmal malformation. RESULTS: Patients at first endovascular treatment ranged from neonates to 157 months (median age, 4.3 months). Patients with preinterventional fine, vascular network formations were significantly older at the initial angiogram than patients with postinterventional fine, vascular network formations (P < .05). On average, for 20 control choroidal/mural vein of Galen aneurysmal malformations whose treatment course had been completed and in which no plexiform network was visualized, a mean of 2.63 (SD, 1.64) treatments were required to achieve a radiographic cure. For the 36 choroidal/mural vein of Galen aneurysmal malformations whose treatment course had been completed and in which a fine, vascular network formation was visualized, a mean of 5.94 (SD, 2.73) treatments were required to achieve a radiographic cure (P < .01). CONCLUSIONS: Development of a fine, vascular network formation is an acquired and reversible phenomenon that differs from typical dural vessel recruitment, given the hairlike nature of the network and its rapid onset postinterventionally. It typically resolves after completion of treatment, and this resolution correlates with closure of the vein. We recommend that neurointerventionalists avoid delays in treatment wherever possible to reduce the likelihood of a fine, vascular network formation.

State of the art of antenatal diagnosis and management of vein of Galen aneurysmal malformations.

Vein of Galen aneurysmal malformation (VGAM) is a severe rare vascular anomaly whose prognosis depends on cerebral and cardiac consequences that can be hard to diagnose, let alone predict in utero. We performed an updated review to summarize current research on the genetics, ultrasound and MRI of VGAM that could help in the diagnosis and management of VGAM. Prenatal diagnosis of VGAM has greatly improved in recent years. Ultrasound allows in utero detection of VGAM in most cases now and is the best exam for prenatal cardiac evaluation. Tricuspid insufficiency is the only cardiac feature associated with poor prognosis. Cardiomegaly may indicate a risk of cardiac failure at birth and should prompt discussion of birth in a specialized facility. Ultrasound can identify constituted cerebral lesions, but MRI diagnoses early signs of cerebral hemodynamic changes, notably through the detection of pseudo-feeders. Genetic exploration should be proposed after VGAM diagnosis. Ultrasound and MRI are essential complementary tools for the diagnosis of VGAM, but also for prognostic evaluation, and provide information for the counseling of parents and optimal management of the pregnancy.

Percutaneous transuterine fetal cerebral embolisation to treat vein of Galen malformations at risk of urgent neonatal decompensation: study protocol for a clinical trial of safety and feasibility.

INTRODUCTION: Although endovascular techniques have improved outcomes in vein of Galen malformations (VOGM), there is still a high rate of morbidity and mortality, particularly among cases with decompensation in the neonatal period. The dimension of the draining venous sinus on fetal imaging correlates with the risk of neonatal decompensation. In fetuses within this high-risk group who do not have end-organ injury, there is a theoretical therapeutic opportunity to reduce the arteriovenous shunt before the normal physiological changes of birth precipitate decompensation. This study investigates the safety and potential benefit of treating a VOGM in utero, which has not been previously studied. METHODS AND ANALYSIS: This study aims to enroll 20 subjects: pregnant women with a fetus harbouring a high-risk VOGM (defined on MRI by a narrowest medial-lateral width greater than 8 mm in the draining venous sinus). Unfortunately, the subset of fetuses with in utero end-organ injury is ineligible, because the late stage of pathology is not amenable to recovery from a cerebrovascular intervention, likely not even in utero. This study aims to alter the physiology before such developments accrue.At or after 23 weeks of gestation, a transuterine transposterior fontanelle needle puncture to the torcular allows ultrasound-guided deployment of coils to embolise the draining venous malformation.This study has 97.5% power to detect major safety events at 30% or greater, and 80% power to detect a reduction in the rate of neonatal intervention from 80% to 30%. In the staged study design, an interval evaluation after 11 patients invokes study termination if safety events occur above the allowed threshold. ETHICS AND DISSEMINATION: The institutional review boards at Mass General Brigham and Boston Children's Hospital (BCH) reviewed and approved this protocol. The BCH Department of Radiology and a patient family philanthropic donation fund this study. The trial results will be published in peer-reviewed journals and presented at scientific conferences. TRIAL REGISTRATION NUMBER: NCT04434729.

Unrepaired Maternal Vein of Galen Malformation in Pregnancy: A Case Report.

We present a case of a pregnant patient with an unrepaired vein of Galen malformation (VGAM) and left ventricular (LV) dilation. Patients with VGAM lesions typically present during childhood with cardiac failure or developmental delay prompting embolization. Therefore, it is highly unusual for an adult to present with an unrepaired lesion.1 It poses challenges for obstetric and anesthetic management during pregnancy and delivery to reduce the risk of heart failure, arrhythmia, and intracranial hemorrhage. Our patient safely delivered a term neonate by cesarean delivery with neuraxial analgesia at a Level IV Maternal Care Center.

Transvenous embolization of vein of galen aneurysmal malformations using the "Chapot pressure cooker" technique.

METHODS: Two patients, one 5-year-old and one 7-year-old, both presented with congestive heart failure in the newborn period and were subsequently treated in the newborn period with multiple, staged TAEs with n-BCA for choroidal VGAMs. RESULTS: We achieved progressive reduction in shunting and flow but were unable to accomplish complete closure of the malformation: in both patients, a small residual with numerous perforators persisted. The decision was made to perform TVE using the CHPC. In this technique, a guiding catheter is placed transjugular into the straight sinus (SS). One or two detachable tip microcatheters are advanced to the origin of the SS. Another microcatheter is advanced and the tip placed between the distal marker and the detachment zone of the former. Coils and n-BCA are used to prevent reflux of Onyx. CONCLUSIONS: In this study, we recognized two important factors of traditional VGAM treatment that may cause interventionalists to consider the ChPC to treat VGAM: (1) without liquid embolic, deployed coils may not occlude the fistula entirely. (2) There is the concern of causing delayed bleeding should the arterial component of the fistula rupture. ChPC ameliorates these issues by offering complete closure of the fistula with liquid embolic material in TVE.

Extra corporeal membrane oxygenation support for neonatal vein of Galen aneurysmal malformation: Case report.

BACKGROUND: The vein of Galen aneurysm (VGAM) is the most common type of arteriovenous malformation in the neonate. These neonates commonly present with high output cardiac failure that may be associated with pulmonary hypertension. The medical management and stabilization of these neonates can be challenging before staged transarterial embolization of the aneurysm is undertaken. CASE: A 2.34 kilogram neonate, antenatally diagnosed to have VGAM, was born at 36 weeks of gestation for fetal distress. The neonate failed to respond to medical management including inotropes, high frequency mechanical ventilation and inhaled nitric oxide. The patient's high-output heart failure and persistent pulmonary hypertension were stabilized with veno-arterial extra-corporeal membrane oxygenation (VA-ECMO) using central cannulation. Further transarterial staged embolization of the VGAM was undertaken on VA-ECMO support. CONCLUSION: There may be a role of VA-ECMO using central cannulation to optimize management of high output cardiac failure and persistent pulmonary hypertension in neonatal VGAM patients who fail medical management to facilitate staged transarterial embolization of the VGAM.

Review on the current treatment status of vein of Galen malformations and future directions in research and treatment.

INTRODUCTION: Vein of Galen malformations (VOGMs) represent a rare pathologic entity with often catastrophic natural history. The advances in endovascular treatment in recent years have allowed for a paradigm shift in the treatment and outcome of these high-flow shunts, even though their pathogenetic mechanisms and evolution remain in part obscure. AREAS COVERED: The overall management of VOGMs requires a tailored case-to-case approach, starting with in utero detection and reserving endovascular treatment for indicated cases. Lately, the advances in translational research with whole-genome sequencing and the coupling with cellular-level hemodynamics attempt to shed more light in the pathogenesis and evolution of these lesions. At the same time the advances in endovascular techniques allow for more safety and tailored technical strategy planning. Furthermore, the advances in MRI techniques allow a better understanding of their vascular anatomy. In view of these recent advances and by performing a PUBMED literature review of the last 15 years, we attempt a review of the evolutions in the imaging, management, endovascular treatment and understanding of underlying mechanisms for VOGMs. EXPERT OPINION: The progress in the fields detailed in this review appears very promising in better understanding VOGMs and expanding the available therapeutic arsenal.