CPT code 33770 identifies a specialized congenital cardiac operation—an arterial switch with resection of an obstructive pulmonary infundibular muscle—used to correct ventriculo-arterial discordance where the aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle. This complex surgical repair restores normal circulation and relieves obstruction without enlarging a ventricular septal defect. Nationally, this code represents high-acuity, resource-intensive pediatric cardiothoracic care performed predominantly in inpatient surgical settings and tertiary pediatric centers.

Key payers covered in this overview include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise clinical and billing orientation to the procedure, an explanation of typical service context and site of care, and identification of common modifiers used with the code. The summary highlights what stakeholders need to know about clinical intent, common billing considerations, and where to look for additional payer-specific policy details. This information is aimed at hospital coding teams, revenue cycle managers, and clinicians seeking a clear, national-level description of the service associated with CPT code 33770 and the billing context surrounding complex congenital heart surgery.