CPT code 93598: Cardiac output measurement, congenital heart catheterization2026 Medicare rate & RVUs in California

CMS doesn’t publish an office rate for 93598 in California.

Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.

What 93598 covers

This add-on reports cardiac output measurement performed during cardiac catheterization for congenital heart disease. It accompanies the applicable congenital catheterization service rather than identifying the catheterization itself or a separate angiographic study. Codes 93593–93597 identify the primary right-heart, left-heart, or combined catheterization, with distinctions for native cardiac connections where applicable. The physician performing the catheterization reports the measurement with that primary service.

Medicare lists 93598 as carrier priced (status C): CMS publishes no national payment, and the Medicare Administrative Contractor sets payment for each claim. As an add-on, it is billed only with a primary procedure and is paid within that procedure’s global period. For this diagnostic test, modifier 26 identifies professional interpretation and modifier TC identifies the technical service, including equipment and staff; without either component modifier, reporting represents the global service.

This summary was written with AI assistance from CMS physician fee schedule data and checked against the CMS billing rules shown here. Rates on this page come directly from CMS files.

Where 93598 pays more and less in California

The same RVUs, adjusted for each area’s costs. Open a locality for its calculation, history and nearby areas.

29 of 29 payment localities

How the 93598 rate is calculated

Each of 93598’s three RVUs is multiplied by a geographic index (GPCI) for the payment locality, added up, and multiplied by the conversion factor. Drag the indexes or enter a ZIP to see what moves the rate.

Payment rules and modifiers for 93598

The CMS indicators that decide how 93598 is paid alongside other services.

What modifiers do to the payment

When to use modifier 26

93598 compared with similar codes

How to choose

93593Right heart cathNormal connections

93593 reports primary right-heart catheterization for congenital heart disease with normal native connections. 93598 reports cardiac output measurement and is added to the applicable catheterization procedure.

93594Right-heart catheterizationAbnormal native connections

93594 is the primary right-heart catheterization code for congenital heart disease with abnormal native connections. Use 93598 for cardiac output measurement performed during that catheterization.

93595Left heart cathCongenital heart disease

93595 reports the primary left-heart catheterization service for congenital heart disease. 93598 describes the accompanying cardiac output measurement, not the catheterization.

93597Combined heart cathAbnormal native connections

93597 identifies combined right- and left-heart catheterization for congenital heart disease with abnormal native connections. 93598 is an add-on for cardiac output measurement during the procedure.

Codes related to 93598

Related codes aren’t interchangeable: bill the code that matches the service performed.

Where these rates come from

FeeBase calculates base physician payments from CMS work, practice-expense and malpractice RVUs, adjusted by each locality’s geographic indexes and the conversion factor. Services without a published rate are labeled, never given a made-up amount. Amounts are Medicare allowed amounts before claim adjustments: not a patient’s bill or a commercial rate.

CMS RVU26D · effective Oct 1, 2026 through the day before Jan 1, 2027

Open CMS sourceHow we calculate rates