A Child Caught Is A Child Saved: Merging Clinical Testing & Genetic Discovery

January 31, 2019
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Dr. Webster with a patient.

Studying sudden death in young people means partnering with families who have suffered an unexpected tragedy. From the process of listening to these families and studying their heart’s health, new learning can emerge.

Lurie Children’s pediatric cardiologist Gregory Webster, MD, MPH, is leading an effort to explore the genetic link between otherwise healthy young people who have died suddenly and the family members who survive them.

“When a child dies suddenly and unexpectedly, the whole family is devastated,” says Dr. Webster. “We know that some of these events are due to genetic changes that can be passed from parent to child. Our goal is improve our understanding of these conditions and to determine whether other family members are at risk for a future event. Our goal is to use information from in-person visits and clinical tests, as well as genetic information and family participation, to help surviving family members determine the remaining risk of sudden death in their family. We want to prevent a second event.”

To support this effort, Dr. Webster and his team of clinicians, researchers and genetic counselors at Lurie Children’s and Northwestern University Feinberg School of Medicine have developed a national collaboration between 228 medical examiner’s and coroner’s offices in 16 states. The Northwestern Sudden Cardiac Death Collaboration processes and analyzes the genetic code (DNA) of children and young people between the ages of 1 and 40 who have died suddenly. The team also reaches out to the families to see if first-degree relatives would be interested in participating in clinical and genetic follow-ups.  The team then brings both the genetic test results and the clinical results together to determine the family’s risk for a future event.

“Many studies have collected DNA from cases of sudden death,” says Dr. Webster. “We hope that one of our contributions is to extend the DNA analysis further by understanding the clinical circumstances of the sudden death and by using information from the families to determine how that information applies to surviving parents, siblings and children.”

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A genetic anomaly has caused fat (small white circles) to replace normal muscle tissue (red) in this heart. Disruptions in the architecture of the heart rhythm system contribute to life-threatening rhythm disorders. 

In some instances, a sudden death can be prevented by quick action. In Jim Murray’s case, at 35 and considered otherwise healthy, he experienced a potentially fatal heart rhythm episode at his office. Thanks to a fast-acting security guard who knew CPR, his abnormal heart rhythm was controlled in time to get him to a hospital for treatment. He was diagnosed with left ventricular arrhythmia, an uncommon condition and one that is usually fatal.

With his survival came questions and a deep dive into his medical history. 

“As it turns out, my history of light-headedness and numerous fainting spells could have been an early indicator,” says Jim. “However, EKGs taken at the time showed no problems. The consistent message was that nothing was wrong. But if high quality genetic testing had been available in the 1970s, this could have been diagnosed much earlier.”

Jim’s own two children have received full genetic work-ups. The results showed that his 15-year-old son has one of the same two markers in his genome as Jim. One of them is associated with heart disease in children and young adults, but not necessarily with sudden death. While his son does not require any interventions at this point, this genetic information guides his physicians in decisions about future screenings. “We are watching him closely,” says Jim.

When his sister began having fainting spells, because of her family risk profile she received an implantable cardioverter-defibrillator like Jim has, to regulate her heart’s rhythm, if necessary.

In addition, her 8-year-old daughter, who has had repeated fainting spells, is also being watched. Eventually, genetic testing was performed for other members of Jim’s family, and their risks were judged to be lower. 

“Our goal is to eventually define markers of risk before a sudden cardiac event occurs,” says Dr. Webster. “As we work toward that goal, we hope that our improved understanding of the connection between genetics and sudden cardiac death provides families and doctors with better tools to assess risk in families who are affected by these potentially tragic events.”

Jim supports Dr. Webster’s research through philanthropy, and is passionate about its importance. “This is an incredibly traumatic experience,” he says. “It is so important to be able to do high-quality diagnostic genetic testing in early childhood. We need many more samples to help us understand this phenomenon. We need to develop new science, and Dr. Webster is working on that. The child caught is the child saved.”