CPT code 33501 represents surgical ligation or closure of a coronary artery fistula performed without cardiopulmonary bypass. This procedure addresses abnormal vascular connections between a coronary artery and a pulmonary vein or a cardiac chamber to reduce risks such as thrombus, endocarditis, and aneurysm rupture. Nationally, the code is relevant to cardiac surgeons, hospital billing operations, and payers managing high-acuity cardiovascular encounters.

Key payers discussed include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise clinical context for the procedure, typical settings where it is performed, and the payer landscape covered in the analysis. The publication outlines benchmarking considerations, common billing modifiers associated with cardiac surgical services, and the clinical rationale that supports use of the code.

The content is intended to help coding and revenue cycle staff, clinical leaders, and policy analysts understand what CPT code 33501 denotes, where the service is typically delivered, and which major commercial and public payers are relevant to reimbursement and coverage discussions. Data not available in the input is clearly noted where applicable.