New Publication in Journal of the American College of Cardiology

This brief report asks a fundamental question for anyone using administrative claims data in cardiovascular research: how accurately do Medicare billing codes capture surgical procedural details? Conduit counts from Medicare CPT codes, ICD-10 codes, and the STS Adult Cardiac Surgery Database (STS-ACSD) were each validated against surgeon-dictated operative notes as the reference standard – with abstraction supported by both trained researchers and a large language model (GPT-4.1-mini). CPT codes demonstrated strong agreement with operative notes (95.3% overall), performing comparably to the STS-ACSD (92.4%) and outperforming ICD-10 codes (89.4%), which showed notably lower concordance for multiarterial graft counts.

Publication details

Erez E, Squiers J, Banwait J, Dorton C, Gasparini A, Kim A, DiMaio J, Schaffer J, and the THH Medicare Working Group. Validation of CABG Conduit Counts in Medicare Claims Using Operative Notes and the STS Database. Journal of the American College of Cardiology 2026.

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