CPT code 33647 denotes surgical closure of defects in the atrial and ventricular septa using sutures or patch material to prevent intracardiac mixing of oxygenated and deoxygenated blood. This open cardiac procedure is a key intervention for significant congenital or acquired septal defects and carries important implications for perioperative resource use, inpatient care pathways, and clinical outcomes across the U.S. healthcare system. Key payers included in the analysis are Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare.

Readers will find a concise clinical context for the procedure, typical sites of service, and the service line classification. The publication provides payer-aligned benchmarks and coverage considerations, highlights common billing modifiers, and situates 33647 within related cardiac surgical services to aid coding and claims adjudication. It also outlines how this code relates to resource utilization in inpatient cardiac surgery settings and what aspects of documentation and coding commonly affect reimbursement and compliance reviews. Data not available in the input is noted where applicable.