Ventricular septal defect with silent discrete subaortic stenosis.

Area of Science:

• Cardiology
• Pediatric Cardiology
• Congenital Heart Disease

Background:

• Subaortic stenosis (SAS) is infrequently associated with ventricular septal defects (VSD).
• Diagnosis of coexisting SAS and VSD presents significant challenges.

Observation:

• Four patients with discrete SAS adjacent to VSD were studied.
• In three cases, SAS was clinically silent and undetected during initial cardiac catheterization and angiocardiography.
• Post-VSD closure, a murmur suggested residual VSD, but later findings indicated acquired SAS.

Findings:

• Peak systolic pressure gradients across the SAS ranged from 45 to 145 mmHg in three patients.
• Reoperation revealed a discrete subaortic shelf opposite the VSD closure patch.
• Echocardiography and cardiac catheterization diagnosed SAS in the fourth patient preoperatively.

Implications:

• Discrete subaortic shelves adjacent to VSDs can be asymptomatic and diagnostically elusive.
• Failure to identify and resect SAS during VSD repair can lead to severe acquired subaortic obstruction.
• Comprehensive pre-operative assessment and intraoperative vigilance are essential for managing these complex congenital heart defects.