Discrete subaortic stenosis: a study of 20 cases

Area of Science:

• Cardiology
• Pediatric Cardiology
• Interventional Cardiology

Background:

• Discrete subaortic stenosis (DSS) is a congenital heart defect causing left ventricular outflow tract obstruction.
• Membranous obstruction is the most common form of DSS, often presenting with significant pressure gradients.

Purpose of the Study:

• To evaluate the efficacy of different treatment modalities for discrete subaortic stenosis.
• To assess the long-term outcomes of balloon dilatation for membranous subaortic stenosis.

Main Methods:

• Retrospective review of 20 patients with discrete subaortic stenosis over 11 years.
• Diagnostic imaging included cross-sectional echocardiography and angiography.
• Intervention assessment involved balloon dilatation for membranous obstruction.

Main Results:

• Membranous obstruction was identified in 85% of patients.
• Balloon dilatation in 8 patients with membranous obstruction significantly reduced peak systolic gradients (107.1 to 32.3 mm Hg).
• Hemodynamic benefits of balloon dilatation were sustained for a mean of 9.6 months.

Conclusions:

• Balloon dilatation is a safe and effective treatment for thin subaortic membranes.
• Surgical resection remains necessary for fibromuscular collar or tunnel-type subaortic obstructions.