CPT code 93306: Echocardiography, complete with Doppler and color flow

What is CPT Code 93306?

CPT 93306 is used for a comprehensive transthoracic echocardiography procedure that includes spectral Doppler echocardiography and color flow imaging. This non-invasive test allows healthcare providers to assess cardiac structure and function, identify acute myocardial infarction, and evaluate conditions such as valvular heart disease, cardiomyopathy, and pericardial effusion to help ensure patient safety.

The spectral Doppler component measures blood flow velocity and direction, while the color flow imaging detects abnormalities like regurgitation or stenosis. CPT 93306 also helps determine ejection fraction, wall motion abnormalities, and diastolic dysfunction. To ensure accurate billing, it’s important to indicate whether the claim includes professional and technical components or only the technical component. Modifiers may be required to document a distinct procedural service if performed on the same day as stress echocardiography.

CPT code 93306 documentation requirements

To support billing for echocardiography services under CPT code 93306, comprehensive and compliant documentation must be maintained in the patient’s medical record. The following elements are required:

• Medical necessity: The record must clearly demonstrate medical necessity, including relevant medical history, physical examination findings, and the rationale for ordering the study. Acceptable indications include symptoms such as chest pain, heart murmur, shortness of breath, suspected heart failure, or other cardiac abnormalities.
• Clinical indication and diagnosis: A valid ICD-10-CM diagnosis code must be reported that best reflects the patient’s condition. For diagnostic tests, report the result if known; if not, document the symptoms prompting the test. Claims without a valid diagnosis code will be considered incomplete under Section 1833(e) of the Social Security Act.
• Referring/ordering physician: The referring or ordering physician’s name and NPI must be included on the claim for Medicare billing.
• Comprehensive report: Each service must include a formal written report signed by a qualified physician, typically a cardiologist. The report should contain:
  • Detailed 2D and/or M-mode measurements include LV end-diastolic and end-systolic diameters, wall thickness, left atrial diameter, and aortic valve excursion.
  • A qualitative or quantitative assessment of left ventricular function (e.g., ejection fraction, LV volumes, or mass measurements).
  • Documentation of Doppler interrogation techniques used (spectral and/or color Doppler) and their findings, including blood flow patterns, regurgitation, or stenosis.
  • Clear interpretation and diagnostic impression, correlating findings with the patient’s clinical presentation.
• Image documentation: Copies of all echocardiographic images (paper or digital) must be retained and made available upon request.
• Repeat testing justification: If tests are repeated, documentation must include reasons for the repeat study and reference prior results. This should be noted if prior test results were unavailable despite a good-faith effort to obtain them.
• Limitations to exercise stress testing: If CPT 93306 is part of a pharmacologic stress echocardiogram instead of exercise testing, the record must explain why exercise testing was not feasible based on patient history and physical findings.
• Qualified personnel: Documentation verifying the credentials of individuals performing the echocardiography, as outlined in the Medicare LCD, must be available upon request.

CPT code 93306 billing guidelines

When billing for CPT 93306, providers must adhere to the following billing rules and coding considerations:

• Bundled services: Under the National Correct Coding Initiative (NCCI), CPT 93306 includes 2D imaging, M-mode, spectral Doppler, and color flow Doppler. Therefore, separate billing for codes 93320 or 93325 is not permitted when performed as part of this comprehensive exam.
• Modifiers: Modifier 26 should be appended when billing for only the professional component, which includes interpretation and reporting. Modifier TC is used when billing only the technical component (equipment and technician). If multiple procedures are performed on the same day and are distinct services, modifier 59 may be appropriate—documentation must support the separation.
• Diagnosis coding: A valid diagnosis code must accompany the claim. If the test result is known, report the definitive diagnosis. If the test is inconclusive, report the symptom or condition that prompted the study.
• Contrast studies: If contrast agents are used during the echocardiography, the medical record must document that conventional imaging was insufficient and that contrast was necessary for diagnostic clarity.
• Audit readiness: All documentation, including reports, images, prior study comparisons, and clinical notes, must be available for Medicare review upon request.

Other relevant CPT codes

• 93308: Transthoracic echocardiography, limited or follow-up study
• 93320: Spectral Doppler echocardiography
• 93325: Color flow Doppler echocardiography
• 93351: Stress echocardiography, including baseline and continuous supervision