Keeping the (heart)beat strong after pediatric disease

Sickle cell disease causes red blood cells to clump together and clog blood vessels, potentially resulting in heart injury and myocardial fibrosis (scar tissue buildup). “Sickle cell disease chips away at the wall of your health one brick at a time,” said Akshay Sharma, MBBS, MSc, Department of Bone Marrow Transplantation & Cellular Therapy.

Bone marrow transplantation can be used to cure sickle cell disease, but myocardial fibrosis was thought to be unaffected by tranplantation. Research published in Blood by Sharma and collaborators showed that not only did heart function recover, but also myocardial fibrosis damage was reversed, which no disease-modifying treatment has previously achieved.

Early detection reduces long-term risk

Cardiovascular risk is also increased in survivors of pediatric cancer and may not be fully realized until the survivors are older. A study in The Lancet Oncology led by Gregory Armstrong, MD, MSCE, Department of Epidemiology & Cancer Control chair, showed that by age 50, survivors experience a cumulative incidence of major adverse cardiovascular events (MACE) almost 20 times higher than that of the average population. Frequent screening detects this increased risk for MACE; thus, proactive screening by electrocardiogram or echocardiography may improve risk management. “Clinicians need to be aware that cancer survivors are at higher risk than the general population,” said Armstrong. “They should screen survivors appropriately and maintain a low threshold for referral to a cardiologist.”

Early detection can also help prevent other long-term heart risks among survivors. In the Journal of Clinical Oncology, Stephanie Dixon, MD, MPH, Department of Oncology, showed a high prevalence of prediabetes in young adult survivors, which increases their risk of diabetes and related cardiovascular and kidney disease.  

“We need to help survivors understand that prediabetes is an early warning sign that should lead to a change, whether that’s lifestyle, medication, or close primary care follow-up,” Dixon said. “But that change starts with physicians identifying when a survivor has developed prediabetes.”

Preventing heart disease before it manifests

Estimating the risk of cardiovascular diseases is not straightforward, as many of those conditions are asymptomatic until a severe event occurs. In a study published in the Journal of Clinical Oncology, Matthew Ehrhardt, MD, MS, Department of Oncology, showed that two common biomarkers, global longitudinal strain (GLS) and N-terminal-pro-B-type natriuretic peptide (NT-proBNP), can identify survivors with normal-appearing heart function who are at elevated risk of heart disease.

GLS, which is a measure of the heart muscle’s ability to contract and relax with each cycle, can be determined via echocardiogram. NT-proBNP is a serum biomarker released into the bloodstream when the heart is injured or overworked.

“The increased risk of developing cardiac dysfunction observed in individuals with abnormal GLS and NT-proBNP supports investigating early interventions to prevent heart failure progression,” said Ehrhardt. 

By studying the impact of treatments, early detection, and interventions, St. Jude researchers are making significant strides toward preserving and protecting the heart health of survivors of pediatric diseases.