Aortic valve replacement in children: are mechanical prostheses a good option?

Area of Science:

• Pediatric Cardiology
• Cardiovascular Surgery
• Biomaterials Science

Background:

• Aortic valve lesions in children present complex management challenges.
• The optimal prosthetic valve choice for pediatric aortic valve replacement (AVR) remains debated.
• Mechanical prostheses are a potential option for irreparable aortic valve disease in pediatric patients.

Purpose of the Study:

• To evaluate the early and late clinical outcomes of AVR using mechanical prostheses in pediatric patients.
• To assess the safety and efficacy of mechanical aortic valves in a pediatric cohort.
• To compare the long-term results of mechanical AVR with other available treatment options in children.

Main Methods:

• A retrospective analysis of 56 pediatric patients (mean age 11.2 years) who underwent AVR with mechanical prostheses.
• Patients received long-term anticoagulation with warfarin to maintain an INR of 2.5-3.0.
• Mean follow-up was 7.3 years, with a maximum of 26 years, encompassing 405 patient-years.

Main Results:

• Operative mortality was 5.3%. Late events included valve thrombosis, stroke, and paravalvular leak, with freedom from thromboembolism at 20 years at 93%.
• Actuarial survival at 20 years was 84.9%. Re-operation was required in 8.9% of patients, none due to valve outgrowth.
• Post-operative NYHA functional class improved significantly, with 90% of patients in NYHA class I or II at latest follow-up.

Conclusions:

• Mechanical AVR, particularly with aortic root enlargement when needed, is a safe and effective treatment for children with irreparable aortic valve lesions.
• The procedure is associated with acceptable operative risk, low rates of late complications, and favorable long-term survival.
• Mechanical aortic valves represent a strong alternative to biological substitutes in the pediatric population, including the Ross procedure.