Keywords vein of Galen malformation - high-output heart failure - endovascular embolization
Vein of Galen malformation (VGM) was first described in 1895 as an abnormal fistula
between the cerebral arteries and the great vein of Galen.[1 ]
[2 ] Neonates with VGM usually present with cardiac failure and cyanosis, and can be
mistaken as having cyanotic congenital heart diseases. Without intervention the mortality
rate among infants with VGM is close to 100%.[3 ] Endovascular embolization revolutionized the management of VGM and significantly
reduced its morbidity and mortality.
Case Report
The patient was a 3280-gram newborn female born at 35 weeks gestation. Apgar scores
were 7 and 9 at 1 and 5 minutes, respectively. The patient developed early respiratory
distress, mild cyanosis (O2 saturation 88%), and required endotrachial intubation. Initial cardiac examination
showed hyperdynamic precordium and a faint systolic murmur. Chest X-ray showed cardiomegaly
and diffuse opacification of both lungs. Surfactant and nitric oxide were administered
with the assumption that the patient had respiratory distress syndrome and persistent
pulmonary hypertension of the newborn.
The patient developed increased tachycardia (heart rate of 195/minutes), metabolic
acidosis, and decreased urine output. An audible bruit was heard upon head auscultation.
An echocardiogram showed normal cardiac anatomy, hyperdynamic function (systolic function
[SF] 55%), and a large patent ductus arteriosus (PDA) with a bidirectional shunt flow.
There was retrograde flow in the distal aortic arch to the dilated neck vessels ([Fig. 1 ]) and pulmonary hypertension (65 mm Hg). Ultrasonography and computed tomography
of head confirmed the presence of a large VGM (2.81 × 1.65 cm) with high velocity
turbulent flow.
Figure 1 Doppler of the aortic arch showing retrograde flow in the descending aorta.
The renal and cardiac function deteriorated (SF 25%), and a strain pattern was noted
in electrocardiogram (EKG). On the third day of life, angiography revealed a large
VGM ([Fig. 2A ]). Transarterial embolization was performed using Guglielmi detachable coils, resulting
in a substantial decrease in VGM flow.
Figure 2 Angiograms of the vein of Galen malformation and the feeder arteries (A) pre-embolization
and (B) postembolization, with improvement in filling of cortical arteries.
Initial clinical improvement was achieved, but the renal function continued to decline.
On the ninth day of life, the VGM was reassessed and transvenous embolization was
performed. Postembolization angiogram showed a significant decrease in shunting through
the VGM and improved cortical artery flow ([Fig. 2B ]).
The hospital course which lasted 2.5 months was complicated by preprocedural clinical
sepsis, renal failure, and persistent PDA requiring surgical ligation, and postprocedural
seizures, chylothorax, pericardial effusion, and osteomyelitis of the right femur.
Serial electroencephalograms (EEGs) showed improvement and the last EEG before discharge
had no seizure activity. The chylothorax was treated with chest tube drainage, Portagen
formula (Mead Johnson Nutrition, Glenview, IL), and octreotide.[4 ]
The patient did remarkably well despite of all these complications. At 26 months,
she was seizure free, had a normal physical examination and age appropriate milestones.
An echocardiogram showed normal cardiac anatomy and function.
Discussion
VGM is a rare anomaly of the cerebral vasculature that results in significant aneurysmal
dilation of the great vein of Galen. The clinical presentation of VGM varies with
age. Neonates usually have multiple fistulae and present in high-output cardiac failure.[5 ] Infants and younger children have a single fistula and present with seizures, hydrocephalus,
distention of scalp veins, and failure to thrive. Older children and adults often
present with neurological symptoms of headache and seizure.[6 ] Due to collateral circulation, there is an increased blood flow in the pial veins
leading to subarachnoid and intracranial hemorrhage.[7 ]
High-output cardiac failure in neonates with VGM is multifactorial in origin and responds
poorly to medical management. During fetal life, the low resistance uteroplacental
circulation diminishes the flow through the cerebral circulation. After birth, the
placental circulation is lost and a significant portion of the cardiac output is directed
toward the VGM. There is a compensatory increase in cardiac output and blood volume
to maintain adequate systemic perfusion. This causes significant tachycardia, hyperdynamic
cardiac function, and a wide pulse pressure. Since cardiac perfusion is dependent
on the diastolic time and pressure, the cardiac function eventually deteriorates and
ischemic changes can be noted in EKGs. The perfusion of all organs “including the
brain,” is further compromised by stealing of blood from the systemic circulation
by the low resistance VGM.
The management of VGM progressed through three historical eras. The first era involved
the earliest descriptions of pathology, anatomy, syndromes, and case reports. No interventions
were offered to neonates with VGM and the mortality was close to 100%.[3 ]
During the second era, previously described syndromes were correlated with their outcomes.
The main intervention was a combined open microsurgery through craniotomy and a direct
transtrocular embolization, but mortality and morbidity remained as high as 91% regardless
of surgery or medical management.[8 ]
The third and current phase is the neurointervention era. The development of intravascular
occlusion devices has shown to be safer and more effective. A comparison study showed
death of all six neonates with VGM who underwent direct microsurgery while six of
the eight who were treated with endovascular embolization survived.[9 ] In a case series of 36 VGMs treated with endovascular embolization, the mortality
rate was 13%.[10 ]
Neonatal VGM remains a serious condition that requires early diagnosis and a multidisciplinary
approach of management and intervention. Coordination among neonatologist, pediatric
cardiologist, and interventional neuoradiologist is essential for better patient care
and outcome. Prematurity and the presence of multiorgan failure should not be considered
absolute contraindications for early intervention if the patient can be stabilized
for the procedure.
