CPT code 33720 identifies open surgical repair of a sinus of Valsalva aneurysm or structural dilation in the ascending aorta performed with cardiopulmonary bypass. This code applies to complex cardiothoracic operative management of aortic root or proximal ascending aortic pathology and is relevant to hospitals, cardiothoracic surgery groups, and payers managing high-acuity vascular and cardiac cases nationwide. Key national payers in typical coverage analyses include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare.

Readers will learn the clinical scope of the code, typical service setting and team composition, common billing modifiers and service line associations (where available), and how this procedure is categorized for payer coverage and claims processing. The publication summarizes benchmarks and policy considerations affecting authorization and coverage for complex aortic surgeries, outlines the procedure's place in surgical treatment algorithms, and highlights documentation elements that commonly influence medical necessity reviews. Data not available in the input is noted where applicable.