[Valve prostheses of mitral position in children]

Area of Science:

• Cardiovascular Surgery
• Pediatric Cardiology
• Biomaterials Science

Background:

• Mitral valve replacement in children presents unique challenges due to growth and long-term durability requirements.
• Previous studies have shown variable outcomes for biological and mechanical valves in pediatric populations.
• Understanding long-term performance is crucial for selecting appropriate prosthetic valves in young patients.

Purpose of the Study:

• To compare the long-term efficacy and durability of biological versus mechanical mitral valves in pediatric patients.
• To evaluate survival rates and freedom from complications in children following mitral valve replacement.
• To determine the most suitable valve type for pediatric mitral valve replacement.

Main Methods:

• A retrospective follow-up study of 20 children (<15 years) who underwent mitral valve replacement before August 1983.
• Patients were divided into biological valve (B-group) and mechanical valve (M-group) cohorts.
• Actuarial survival and event-free rates were calculated up to October 1988.

Main Results:

• Ten-year actuarial survival rates were 53.5% for the B-group and 85.7% for the M-group (not statistically significant).
• Biological valves showed calcification and failure between 27-89 months; no biological valves remained functional at 8 years (0% event-free rate).
• Mechanical valves had a 70.6% event-free rate at 10 years (p < 0.025), with three cases of thrombosis and no other complications.

Conclusions:

• Mechanical mitral valves appear more suitable for pediatric patients than biological valves, offering significantly better long-term event-free survival.
• The high failure rate due to calcification in biological valves underscores their limitations in growing children.
• Further research into pediatric valve replacement strategies is warranted to optimize patient outcomes.