A Phase 1/2 interventional study of Propranolol Hydrochloride and Placebo in Postoperative Chylothorax, Congenital Heart Disease and Open Heart Surgery, sponsored by June Wu. Suspended at 1 site in United States. Open to participants aged 7 Days to 18 Years. Per ClinicalTrials.gov, last updated 2026-05-15.
Sponsored by June Wu · Phase 1/2, Interventional, and Treatment
Postoperative chylothorax is a serious complication after open heart surgery for pediatric patients with congenital heart disease (CHD). While it was thought to be mechanical injury to the thoracic duct, recent research demonstrated that there are intrinsically abnormal lung lymphatics in CHD patients, and after open heart surgery, the fluid shifts that occur overwhelms these abnormal lung lymphatics. As a result, postoperative chylothorax occurs. Propranolol has been found to be helpful in resolving postoperative chylothorax very quickly (9 days) in a subset of postoperative chylothorax patients (60%). However, it is not known why some patients respond and some do not. The investigators hypothesize that propranolol is safe to use in this patient population, and that certain clinical factors will predict propranolol response, but more importantly, some clinical factors can be optimize to allow more patients with postoperative chylothorax to respond to and benefit from propranolol. In order to improve the understanding of how propranolol works and to maximize benefit to patients, the investigators propose to perform a prospective, randomized, double-blind clinical trial to learn how to best use propranolol in patients with postoperative chylothorax.
This clinical trial will prospectively enroll eligible patients and randomize them to placebo or propranolol (1:1). This study will aim to enroll 50 patients, randomized to 25 placebo and 25 propranolol treatment. After patients have been consented, registered, and screened, they will be entered into the study. Participants will be randomized to placebo or propranolol in a 1:1 ratio. Randomization will be double-blinded, and each enrolled participant will be given a number and receive coded medication from the research pharmacy. Patients may undergo a screening MR lymphangiogram (MRL) prior to starting treatment. The criteria for an MRL will require that no additional sedation be given, and patient or parent/legal guardian consents to an MRL. Thus, only patients who are already sedated, or who will be able to undergo the MRL without sedation, and who opts in to the MRL will be eligible. Propranolol or placebo will be administered for 9 days after reaching the lowest effective goal dose not to exceed 2mg/kg/day, or maximum tolerated dose, after which the study groups will be unmasked.
Participants who have ≥80% reduction in volume of chylothorax drainage after 9 days of treatment and who received propranolol are identified as "responders". They will be taken off the study officially at this point as no more study interventions will be given. They will be tapered off of propranolol gradually as clinically indicated.
Participants who have ≥80% reduction in volume of chylothorax drainage but who received placebo will be the "natural history cohort". This will serve to demonstrate, as baseline, the percentage of participants who naturally resolve their chylothorax without intervention.
Patients who have \<80% reduction in chylothorax drainage and who received propranolol, will be categorized as initial "non-responders". They will be officially taken off the study.
Participants who have \<80% reduction in chylothorax drainage and who received placebo are considered a control group. They will be given propranolol for 9 days as a single-arm, open study and re-evaluated after a 9-day treatment. After 9 days at goal dosing, they will receive the same treatment as the responders and non-responders in the propranolol-treated group.
1,007 studies on the registry are indexed under Heart Defects, Congenital; 257 are open to participants now.
This study's planned enrollment of 50 is below the median of 60 across 524 interventional studies indexed under Heart Defects, Congenital.
Browse Heart Defects, Congenital studies →This is the only study on the registry with June Wu as lead sponsor.
Counted across the registry records on this site, refreshed daily.
pleural triglyeride (TG) ≥ half of serum TG, or chylomicron positive
Exclusion Criteria:
Placebo suspension will only have Ora-Blend
Drug: Placebo
Subjects will be randomized to receive 2mg/kg/day. Propranolol will be administered orally, either as a tablet or as a solution, in equal divided doses three times a day.
Drug: Propranolol Hydrochloride
Propranolol will be administered as tablets. Participants who are too young to swallow pills will be given propranolol solution.
Also known as: Propranolol, 2-Propanol, 1-[(1-methylethyl)amino]-3-(1- naphthalenyloxy)-, hydrochloride
Placebo suspension will only have Ora-Blend Medication Flavoring and Suspension Vehicle
Also known as: Ora-Blend
Daily heart rates recorded in flow chart and 1 hour after each dose
Safety outcome
Time frame: 24 days
Daily blood pressures recorded in flow chart and 1 hour after each dose
Safety outcome
Time frame: 24 days
Daily glucose levels
Safety outcome
Time frame: 24 days
Expected and unexpected AEs, per patient
Safety outcome
Time frame: 24 days
Days with documented chest tube (# days), CXR
Will also measure the daily output (volume) in the chest tube(s)
Time frame: 24 days
Initial volume of fluid drained (mL, mL/kg/day)
The volume at the initial day of postoperative chylothorax diagnosis
Time frame: Day 0
Days hospitalized
The length of hospital stay, from post-surgery to discharge
Time frame: 6 months
Thyroglobulin (TG) lymphocyte count
The TG count will be analyzed from the postoperative chylothorax fluid.
Time frame: 24 days
Pre-operative and post-operative echocardiogram anatomic findings for patients with 4-chamber hearts
This outcome will be reported as the percent of patients with normal LV function, normal RV function, and normal pulmonary artery pressure.
Time frame: Pre-operative and up to 24 days
Pre-operative and post-operative echocardiogram anatomic findings for patients with single ventricle (SV) physiology
This outcome will be reported as the percent of patients with normal ventricular function and normal pulmonary artery pressure.
Time frame: Pre-operative and up to 24 days
Percent of patients with Type 1 anatomy
Screening MR lymphangiogram: An optional imaging study to define lymphatic anatomy subtype
Time frame: Day 0
Percent of patients with Type 2 anatomy
Screening MR lymphangiogram: An optional imaging study to define lymphatic anatomy subtype
Time frame: Day 0
Percent of patients with Type 3 anatomy
Screening MR lymphangiogram: An optional imaging study to define lymphatic anatomy subtype
Time frame: Day 0
Percent of patients with Type 4 anatomy
Screening MR lymphangiogram: An optional imaging study to define lymphatic anatomy subtype
Time frame: Day 0
Serum albumin
to be extracted from clinical lab results, if available
Time frame: 24 days
White Blood Cell (WBC) count
to be extracted from clinical lab results, if available
Time frame: 24 days
C-Reactive Protein (CRP)
to be extracted from clinical lab results, if available
Time frame: 24 days
Immunoglobulin level
to be extracted from clinical lab results, if available
Time frame: 24 days
AT3 titer
to be extracted from clinical lab results, if available
Time frame: 24 days
Protein S titer
to be extracted from clinical lab results, if available
Time frame: 24 days
Protein C titer
to be extracted from clinical lab results, if available
Time frame: 24 days
Hours on bypass during CHD surgery
The amount of time the participant was on bypass during heart surgery
Time frame: During surgery
Triglyceride level in chylothorax fluid
Triglyceride levels will be measured
Time frame: 24 days
Plan to share: No — The aggregate data can be shared. The plan is not to share individual participant data to protect their privacy.
This study is suspended, as verified in May 2026. You cannot join it, but the record below documents what was studied.
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