Brain MRIs Provide Insight into Cardiac Neurodevelopment

Dr. Henry Cheng, Attending, Cardiac Intensive Care Unit

*Alumnus, 2008-2011, Senior Fellow in Pediatric Cardiac Intensive Care 2012

Children who have heart surgery as infants are more likely to experience cognitive difficulties as they grow up. Research has demonstrated this time and again, but we still do not know all the reasons why. The Boston Children’s Cardiac Neurodevelopment Program is determined to find out more.

Neurodevelopment is a multi-faceted issue, with determining factors ranging from genetics to home environment to childhood illness. Disruptive medical events in the ICU post-cardiac surgery are well-known contributors to cognitive lapse, and quality caregiving at home is also important. Still, even the most diligent parents and caregivers cannot always make a difference. The brain seems to develop differently in congenital heart disease patients. Figuring out exactly what that internal difference is may lead to development of medical measures that can prevent cognitive delay in future patients.

Dr. Henry Cheng of Cardiology, along with Dr. Jane Newburger, has teamed up with Dr. Janice Ware of Developmental Medicine, Dr. Caitlin Rollins and Dr. Janet Soul of Neurology, and Dr. Ellen Grant of Radiology for a groundbreaking research study to better determine brain development and cerebral physiology in patients before and after neonatal cardiac surgery.

The study combines data from three sources: Brain MRIs, near infrared spectroscopy devices (NIRS, now present in our cardiac ICU) and comprehensive neurodevelopmental follow-up. MRIs are performed before surgery and again three months after surgery. NIRS readings are made before surgery, immediately after surgery, and three months out. The NIRS adds information that MRIs cannot capture, such as cerebral oxygen levels and metabolism.

Dr. Cheng reports preliminary evidence that synaptic development in these patients may be delayed. A deeper understanding of cerebral hemodynamics is necessary to sort out why this is happening. “What we want to know next,” he explains, “is how much oxygen goes to the brain? How much of that is actually used, and is there enough?”

Dr. Cheng is optimistic that this study will lead to significant advances in the way physicians approach cardiac neurodevelopment. The first step to finding the right answers? Asking the right questions.