Valen Roa’s family is getting ready to celebrate his first birthday this week with friends and family, plus a pumpkin as a sign of autumn fun. Meanwhile, Johns Hopkins All Children's Hospital is celebrating the advances in clinical care and research that it is helping to lead in pediatric thrombosis (blood clots in the veins or arteries), in honor of World Thrombosis Day on October 13.
Born with life-threatening congenital heart defects, Valen spent his first six months in the Cardiovascular Intensive Care Unit at Johns Hopkins All Children's. Complex congenital heart defects put children at higher risk for thrombosis, because the heart can’t pump blood efficiently through the body. Cardiac surgery, cardiac catheterization through the femoral artery in the thigh/groin, and placement of special catheters called central venous lines can increase the possibility of thrombosis. That’s what happened to Valen, with the first of several clots occurring when he was less than a month old.
“We were surprised to learn that kids can get blood clots,” said Maria, Valen’s mom. “We were very worried, but the doctors kept assuring us that it was going to be OK.” Medication was used successfully to dissolve the clots.
After Valen was able to leave the hospital, Maria had to give him injections of anticoagulant medicine twice a day under the skin to help prevent the clots from growing or breaking loose to the lungs or brain. The bruises that would linger on his legs after the injections were a reminder of their ordeal. Maria quickly grew skilled at administering the medication, and Valen would keep smiling even as he got the shots. “I was really excited when they told me we could stop giving the injections,” she says.
Valen also smiles at his follow-up appointments with pediatric hematologist Neil Goldenberg, M.D., Ph.D., and clinical research coordinator Laurie Barrett, B.S.N., R.N. at the pediatric thrombosis clinic at Johns Hopkins All Children's. Based in St. Petersburg, Goldenberg is associate professor of pediatrics at the Johns Hopkins University School of Medicine and leads the Johns Hopkins Medicine bicampus pediatric thrombosis program. Recognized nationally for his expertise in pediatric thrombosis, he also serves as director of research at Johns Hopkins All Children's, guiding its growing research mission.
"Blood clots aren’t just a problem for adults; they also occur in infants, children and teens,” explains Goldenberg. "They can be a complication of care for a serious illness or condition such as congenital heart disease or cancer, and they are more likely to occur in patients who require a central venous line for administration of medications, blood products, fluids or nutrition.”
Under Goldenberg’s leadership, Johns Hopkins All Children's is the coordinating center for the Prospective Multicenter Evaluation of the Duration of Therapy for Thrombosis in Children (the Kids-DOTT trial) — a randomized, controlled and blinded phase 3 clinical trial that includes nearly 40 major pediatric centers worldwide. “The goal is to determine whether we can safely and effectively reduce the length of anti-clotting therapy by half (from three months to six weeks) for children who have experienced a venous blood clot,” says Goldenberg.
International guidelines that Goldenberg helped to develop for treatment of venous blood clots in children recommend three months of therapy with anti-clotting medications, based mostly on evidence from adult trials performed in the 1990s. "However, we have also suggested that six weeks of treatment may be reasonable in children with clots triggered by a reversible risk factor, such as a central venous catheter or an infection that is being treated successfully. The length of treatment can make a big difference, because anti-clotting medications may cause bleeding. As the largest randomized trial in the field of pediatric venous thrombosis, Kids-DOTT has the potential to define the future standard of care globally on duration of therapy in children with venous thrombosis.”
The trial received key early support from the National Institutes of Health. Most recently, grants from the American Society of Hematology and the All Children’s Hospital Foundation have funded this important research. Nearly 200 children have participated in the trial to date.
A few months after his birthday celebration, Valen will undergo another of the cardiac surgeries needed to correct his severe congenital heart defects. Maria and Carlos, Valen’s dad, now know that yes, kids can get clots. And when they do, they can benefit from Johns Hopkins All Children's role as a leader in the treatment of pediatric thrombosis.
Learn more about a National Institutes of Health Grant that Johns Hopkins All Children's Hospital received to study blood clots in children.