Helping Children's Hearts Recover from Surgery

Heart surgery saves the lives of thousands of children with heart defects each year, but it comes with a price. When children are placed on mechanical heart support - such as cardiopulmonary bypass and extracorporeal membrane oxygenation (ECMO) - it can fundamentally weaken their hearts. The Portman Research Group is investigating what causes this damage, and is developing new ways to protect against it.

The lab is unraveling the metabolic processes that govern how the heart responds to stress and injury and is identifying hormone and nutritional supplements that prevent damage and accelerate recovery. For instance, Portman's team made a key discovery when they found that giving a thyroid hormone called triiodothyronine to infants supported by cardiopulmonary bypass could reduce the time those infants spent on ventilators after surgery. This improves recovery times and reduces patient and parent stress, and may improve long-term outcomes.

The study that yielded this discovery, Triiodothyronine in Infants and Children During Cardiopulmonary Bypass (TRICC), was one of the largest and most successful pediatric clinical trials ever performed. Portman's team is pursuing a Phase III clinical trial to confirm these results.

Building on this research, Portman and his colleagues are conducting studies in animal models to understand exactly how thyroid hormone influences how the heart uses energy. As part of this project, they are investigating how other supplements, including pyruvate and fatty acids, affect cardiac metabolism and influence the recoveries of animal models placed on mechanical support. This research could set the stage for discoveries that further improve the lives of children who undergo heart surgery.

The lab also plans to pursue more clinical trials of thyroid hormone, including studies of whether other, more affordable, thyroid hormone drugs - including Triostat - can improve outcomes in patients with congenital heart disease worldwide.