Intramyocardial Injection of Autologous Umbilical Cord Blood Derived Mononuclear Cells During Surgical Repair of Hypoplastic Left Heart Syndrome

Phase IIb Study of Intramyocardial Injection of Autologous Umbilical Cord Blood Derived Mononuclear Cells During Stage II Surgical Repair of Right Ventricular Dependent Variants of Hypoplastic Left Heart Syndrome (AutoCell-S2)

Researchers want to better understand what happens to the heart when the stem cells are injected directly into the muscle of the right side of the heart during the Stage II palliative surgery for single ventricle patients with hypoplastic left heart syndrome (HLHS) or HLHS variant. Researchers want to see if there are changes in the heart's structure/function following this stem cell-based therapy and compared to children that have not had cell-based therapy.

This is a Phase IIb trial to determine if the delivery of the autologous UCB-MNC product into the myocardium of the right ventricle of the heart at the time of Stage II surgical repair will provide an improvement in cardiac function, reaching growth and developmental milestones, and quality of life, while also providing a reduction in the cumulative days of hospitalization following Stage II surgical repair. Long-term improvement in cardiac function, reaching growth and developmental milestones, reaching Stage III surgical repair pre-op work-up, prolonging time to cardiac transplantation or death, and improving quality of life will also be determined.

Inclusion Criteria:

• Diagnosis of HLHS or HLHS variant with single right ventricular dependent CHD having undergone Stage I surgical repair and undergoing Stage II surgical repair.
• Less than 13 months of age at time of Stage II surgical repair
• Previous participation in the UCB collection protocol with autologous UCB-MNC product that is acceptable for use (treatment arm only)

Exclusion Criteria:

• History of DMSO reaction (treatment arm only).

• Parent(s) and/or legal guardian(s) unwilling to have their child participate or unwilling to follow the study procedures.

• Severe chronic diseases at the discretion of the treating physician.

• Extensive extra-cardiac syndromic features.

• Known history of cancer.

• Any of the following complications of his/her congenital heart disease:

  1. Any condition requiring urgent, or unplanned interventional procedure within 15 days prior to Stage II surgical repair, unless complete and full cardiac recovery is documented by site investigator
  2. Severe pulmonary hypertension (reported in the medical record as >70% systemic pressure)
  3. Other clinical concerns as documented by a site investigator that would predict (more likely to happen than not to happen) a risk of severe complications or very poor outcome, not directly related to the stem cell product or its injection procedure, during or after Stage II surgical repair.