Building upon the success of the first in utero brain surgery for Vein of Galen Malformation (VOGM) reported in 2023, new data published today in JAMA provides further evidence for the potential use of fetal embolization for this condition.
VOGM is the most common type of congenital blood vessel abnormality, in which the earliest arteries that develop in the brain connect directly with the dominant vein in the young brain, rather than nourishing the brain tissue. This causes a tremendous rush of high-pressure, high-flow blood into the veins, putting the fetus at high risk for mortality, heart failure, brain injury, and neurodevelopmental delay. To improve outcomes for patients, a team at Boston Children's Hospital designed a fetal embolization procedure that results in markedly diminished blood flow through the malformation, without blockage, and launched a clinical trial. Outcomes from their first successful procedure were reported in Stroke in 2023.
In this new report in JAMA, the team describes outcomes from the first 7 patients enrolled in the trial; the fetal procedure was successfully completed in 5 of the 7. With standard postnatal care, even at expert referral centers, this high-risk fetal cohort had an expected 90% mortality, with only 9% likelihood of reaching developmental milestones at age 6 months. Notably, the enrolled patients had a dramatic reduction in mortality to 43%, and 3 of the 5 successfully treated patients survived past the neonatal period; all are thriving, without sign of neurodevelopmental delay. The investigators point out that five of the seven enrolled patients had unscheduled deliveries, including three preterm, at a mean of approximately 3 days post-intervention.
"These early results build on the success of our first case, demonstrating the feasibility of fetal embolization for VOGM and strongly suggesting that the procedure is safe and effective, though a full trial needs to be completed in order to draw solid conclusions," says Darren Orbach, MD, PhD, Co-Director of the Cerebrovascular Surgery and Interventions Center at Boston Children's Hospital and PI of the study.
The research team plans to complete a full trial of this approach, weighing potential reduction in mortality, brain injury, and neurodevelopmental delays against an increased risk of unscheduled, preterm delivery.