Echocardiographic evaluation of congenital mitral valve anomalies in children

Area of Science:

• Pediatric Cardiology
• Echocardiography
• Congenital Heart Disease

Background:

• Congenital mitral valve anomalies are rare but significant causes of pediatric heart disease.
• Accurate diagnosis and characterization are crucial for appropriate management.
• Echocardiography is a primary non-invasive tool for evaluating these conditions.

Purpose of the Study:

• To classify and characterize congenital mitral valve anomalies in children using echocardiography.
• To assess the diagnostic accuracy of Doppler ultrasound compared to invasive methods.
• To investigate the association of supravalvar mitral ring with other left ventricular obstructions.

Main Methods:

• Retrospective analysis of 65 pediatric patients diagnosed with congenital mitral valve anomalies over 7.5 years.
• Utilized 2D, color, pulsed, and continuous-wave Doppler echocardiography.
• Compared echocardiographic findings with cardiac catheterization, surgery, and autopsy data.

Main Results:

• Four main types of anomalies were identified: mitral stenosis with 2 papillary muscles (n=24), parachute mitral valve (n=24), isolated cleft (n=10), and double-orifice mitral valve (n=7).
• Supravalvar mitral ring was associated with mitral stenosis or parachute mitral valve, not isolated.
• Increased peak and mean transmitral Doppler velocities were observed in mitral stenosis (p < 0.01).
• Doppler showed fair correlation (r=0.75) for pressure gradients but poor correlation (r=0.57) for valve area calculation compared to invasive methods.

Conclusions:

• Doppler echocardiography effectively diagnoses and differentiates various congenital mitral valve anomalies in children.
• While Doppler correlates well with pressure gradients, its accuracy in calculating mitral valve area is limited compared to invasive methods.
• Supravalvar mitral ring is a secondary finding associated with other obstructive lesions.