Autus Valve Pivotal Study

Prospective, single-arm, multi-center study to evaluate safety and effectiveness of the Autus Size-Adjustable Valve in pediatric patients aged 18 months to 16 years requiring surgical pulmonary valve replacement. The Autus Valve may be expanded pre-implant to match the subject's body size. Subjects will be evaluated prior to the Autus Valve implant procedure, immediately post-implant, at hospital discharge, 30 days, 6 months, and annually through 10 years. The Autus Valve may be expanded post-implant via transcatheter balloon dilation to accommodate growth of the subject. In subjects who undergo a post-implant valve expansion, follow-up will continue for a minimum of 1 year after the post-implant valve expansion procedure.

Inclusion Criteria: Candidates must meet all of the following inclusion criteria to be considered for enrollment in this study. 1. Age 18 months to 16 years. 2. Male or female. 3. Subject has a native or repaired right ventricular outflow tract. 4. Subject has been recommended for surgical pulmonary valve replacement by treating clinical team (cardiologist and cardiac surgeon). 5. Subject has at least one of the following echocardiographic findings: 1. Severe pulmonary stenosis (defined as RV to PA peak instantaneous gradient ≥60 mmHg); 2. Moderate or greater pulmonary regurgitation; 3. Moderate or greater pulmonary stenosis plus moderate or greater pulmonary regurgitation. 6. Subject's body size is suitable for implantation of a study device ranging from 12.7 to 22 mm (internal diameter). 7. Subject and parent/legal representative, where appropriate, are willing to provide informed written consent. 8. Subject and parent/legal representative, where appropriate, and treating physician agree that the subject will return for, and comply with, all required study assessments and follow-up visits. Exclusion Criteria: Candidates will be excluded from the study if any of the following conditions are met: 1. Subject requires valve replacement in a non-pulmonary position. 2. Subject has a prosthetic valve at other valve position or will need a prosthetic valve at other valve position (i.e., anticipate additional valve replacements needed within 3 years). 3. Subject has pulmonary arterial hypertension (defined as mean PA pressure ≥25 mmHg). 4. Subject has pulmonary atresia and major aortopulmonary collaterals. 5. Subject has significant peripheral pulmonary artery stenosis. 6. Subject has an active infection requiring current systemic antibiotic therapy (if temporary illness, subject may be a candidate 4 weeks after discontinuation of antibiotics). 7. Subject has active endocarditis or a history of infective endocarditis. 8. Subject has renal insufficiency as determined by a serum creatinine (S-Cr) level ≥2.5 mg/dL within 60 days prior to the Screening Visit, or has end-stage renal disease. 9. Subject has leukopenia (defined as a white blood cell (WBC) count \