Candidates will be excluded from the study if any of the following conditions are met:

1. Subjects undergoing the Stage I Norwood operation who do not have HLHS.

2. Subjects requiring mechanical circulatory support immediately prior to Stage II BDCPA operation (within 5 days).

3. Parent or guardian unwilling or unable to comply with necessary follow-up(s).

4. Mother is serum positive for HIV 1/2, hepatitis B surface antigen or viremic hepatitis C and Treponema pallidum.

5. Subjects who are unsuitable for inclusion in the study in the opinion of the investigator(s).

The CHILD Trial: Hypoplastic Left Heart Syndrome Study.