Transluminal balloon dilatation for discrete subaortic stenosis

Area of Science:

• Pediatric Cardiology
• Interventional Cardiology
• Congenital Heart Disease

Background:

• Discrete subaortic stenosis (DSS) is a significant cause of left ventricular outflow tract obstruction in children.
• Membranous and fibromuscular forms of DSS present distinct anatomical challenges.

Purpose of the Study:

• To evaluate the efficacy of transluminal balloon dilatation for treating discrete subaortic stenosis in pediatric patients.
• To compare outcomes between membranous and fibromuscular types of DSS.

Main Methods:

• Ten pediatric patients with DSS underwent balloon dilatation.
• 2D echocardiography and cineangiography were used for visualization and assessment.
• Patients were categorized into Group I (thin membrane) and Group II (fibromuscular ring).

Main Results:

• Significant reduction in mean pressure gradient across the obstruction in both groups post-procedure.
• Group I showed a greater reduction in gradient (82 to 22 mm Hg) compared to Group II (155 to 85 mm Hg).
• Obstruction relief persisted at 1-year follow-up in catheterized patients; 3 Group II patients required surgery due to residual gradients.

Conclusions:

• Transluminal balloon dilatation is an effective treatment for pediatric DSS.
• Outcomes are more favorable for patients with thin, membranous DSS compared to fibromuscular obstructions.