Heart Regeneration in Tetralogy of Fallot

Mechanistic Clinical Trial of Beta-blocker Administration for Reactivating Cardiomyocyte Division in Tetralogy of Fallot

Protocol Description

The purpose of this study is to determine whether the medicine propranolol can increase heart muscle cell proliferation and normalize heart growth in infants with Tetralogy of Fallot (ToF), a complex congenital heart condition that requires surgery after birth to repair multiple defects. Research has shown that people with ToF have a diminished ability to generate new heart muscle cells, compared to people without heart disease. Researchers believe that the beta-blocker propranolol may be able to increase heart muscle cell proliferation and normalize heart growth. Propranolol is approved by the Food and Drug Administration (FDA) to treat a certain kind of benign tumor in infants (hemangioma), but it is not currently approved by the FDA to increase heart muscle growth.

Eligibility Criteria

Babies who will be receiving heart surgery for correction of ToF are eligible for this study.
Males and Females: Babies age 1 to 2 months


Leading up to surgery, which usually happens at 3 to 9 months of age, participants will visit the hospital monthly for examinations. At the initial visit, the infant will have an echocardiogram and MRI imaging. Each day thereafter until surgery, participants’ parents/guardians will provide as an orally administered liquid either propranolol or a placebo. On day 7 of enrollment, participants from both the active and placebo groups will additionally receive a 5-day regimen of 15N-thymidine, which helps researchers to quantify heart cell proliferation. Following surgery, researchers will examine heart muscle tissue that is removed normally as part of the corrective procedure looking for signs of increased cell production.
Visits: Monthly until surgery; May occur at time of routine cardiology appointments.
Duration: Up to 11 months, depending on when surgery is scheduled

Status: Enrolls from Current Patient Cases

Source(s) of Support

Richard King Mellon Foundation

Primary Investigator

Bernhard Kühn, MD

Contact Information

For more information about the study, please contact:
Lead Clinical Research Coordinator Shannon Janzef, MSN, RN