Transthoracic echocardiography (TTE) is one of the most commonly performed cardiac imaging studies in the United States. It is non-invasive, fast, and clinically essential for diagnosing structural heart disease, assessing ventricular function, evaluating valvular disorders, and monitoring chronic cardiovascular conditions.
Among all echo CPT codes, CPT 93306 is the most frequently billed and the most widely recognized. Because of its comprehensive nature, payer-specific policies, and documentation requirements, getting CPT 93306 right is critical for clean claims and accurate reimbursement.
This guide explains everything you need to know about CPT 93306—what it includes, when to use it, common mistakes, prior authorization rules, payer nuances, and how to avoid denials.
Improve accuracy and reduce payer denials with our expert CPT 93018 Stress Test Interpretation Billing Guide covering documentation, medical necessity, and interpretation rules.
What Is CPT 93306?
Official CPT definition:
“Echocardiography, transthoracic, real-time with image documentation (2D), with or without M-mode recording; complete, with spectral Doppler echocardiography, and with color flow Doppler echocardiography.”
In simple terms:
CPT 93306 = Complete transthoracic echo (2D + M-mode) + Doppler + color flow mapping.
It is the most complete non-invasive echo CPT code.
Use CPT 93306 only when all three elements are performed and documented:
- 2D echocardiographic imaging
- Spectral Doppler
- Color flow Doppler
If any component is missing or limited, another CPT code (like 93307 or 93308) must be used instead. Ensure cleaner claims for non-Doppler echo studies with our CPT 93307 Echocardiogram Without Doppler Billing Guide updated for 2024–2025 coding and payer requirements.
What CPT 93306 Includes
CPT 93306 requires a full evaluation of multiple cardiac structures and hemodynamic assessments.
Structural components typically included:
- Left ventricle size & function
- Ejection fraction (EF)
- Right ventricle assessment
- Atria (left & right)
- Mitral valve
- Aortic valve
- Tricuspid valve
- Pulmonic valve
- Pericardium
- Aorta (root, ascending)
- IVC/SVC assessment
- Wall motion abnormalities
Doppler components include:
- Mitral inflow velocities
- Aortic outflow velocities
- Tricuspid regurgitation assessment
- Aortic insufficiency
- Pulmonic flow & gradients
- RV systolic pressure estimation (RVSP)
Color flow mapping includes:
- Regurgitant jets
- Flow turbulence
- VSD/ASD detection
- Inflow/outflow visualization
This combination provides a thorough assessment of cardiac structure and function.
When to Bill CPT 93306
Use CPT 93306 when:
✔ A comprehensive echo is performed
(Not a limited study.)
✔ Both spectral Doppler and color flow Doppler are performed and documented
Without Doppler, it is not 93306.
✔ You evaluate multiple cardiac structures
Including ventricles, atria, and valves.
✔ Clinical indications require a complete assessment
Examples:
- Shortness of breath
- Chest pain
- Hypertension
- Heart murmur
- Known/suspected valvular heart disease
- Cardiomyopathy
- Congestive heart failure
- Afib evaluation
- Prior MI
- Monitoring of structural heart disease
✔ Image documentation is saved in the patient record
Lack of stored images = denial.
When NOT to Use CPT 93306 (Use These Codes Instead)
❌ Use 93307
If Doppler OR color flow is NOT performed.
❌ Use 93308
If the study is limited or follow-up only (e.g., check pericardial effusion).
❌ Do NOT use 93306 for contrast-only reassessment
Contrast alone does not require a full Doppler evaluation. Avoid common ECG billing errors by reviewing our comprehensive CPT 93000 12-Lead ECG Billing Guide built to support cardiology practices seeking cleaner claims.
❌ Do NOT use 93306 for stress echo
Use 93350 or 93351.
Accuracy in code selection is the #1 way to avoid denials.
Documentation Requirements for CPT 93306
Patients want clear evidence that a complete echo was performed.
Your documentation must include:
✔ 1. Medical Necessity
Common ICD-10 examples:
- R06.02 – Shortness of breath
- I10 – Hypertension
- R01.1 – Heart murmur
- I50.9 – Heart failure
- I25.10 – CAD
- I48.91 – Atrial fibrillation
- R94.31 – Abnormal ECG
- I42.0 – Dilated cardiomyopathy
✔ 2. Structures Examined
Must include evaluation of:
- LV structure & function
- RV structure & function
- All major valves
- Pericardium
- Atria
- Aorta
✔ 3. Doppler Measurements
Examples:
- Mitral inflow (E, A waves)
- LVOT velocities
- Aortic gradients
- Regurgitant severity gradings
- RVSP estimation
✔ 4. Color Flow Doppler Findings
Examples:
- MR jet
- TR jet
- AI regurgitant flow
- Flow abnormalities
✔ 5. Diagnostic conclusions
Examples:
- Normal LV function
- Mild MR
- Severe AS
- Low EF
- Global wall motion abnormalities
✔ 6. Impression and recommendations
Not required, but strengthens documentation.
✔ 7. Signature of interpreting provider
Electronic or ink.
Incomplete documentation is the leading cause of denials.
Prior Authorization Requirements for CPT 93306
Medicare
- No prior authorization
- Must meet medical necessity
Medicaid
Varies by state:
- Some require PA for imaging
- Others allow echo without PA if medically necessary
Commercial Payers
Most do NOT require prior authorization for a TTE unless:
- The plan has cardiology imaging restrictions
- The patient is in a managed-care/HMO plan
- The test is repeated within a short interval
Plans that often require PA:
| Payer | PA Likely? |
| Aetna | Sometimes |
| Cigna | Sometimes |
| UHC | Often (depending on policy) |
| Anthem/BCBS | Variable |
| Humana | Sometimes |
| HealthNet | Often |
If authorization is required, the echo should not be billed without approval. Improve accuracy for 24-hour cardiac monitoring with our CPT 93224 Holter Monitor Billing Guide including documentation, hooks, interpretation rules, and NCCI edits.
Common Denials for CPT 93306
❌ 1. Missing Doppler or color flow documentation
If only 2D imaging was done → should bill 93307.
❌ 2. Insufficient medical necessity
Examples:
- No cardiovascular symptoms
- Routine echo without an indication
❌ 3. Documentation is inconsistent with a “complete” study
Missing structures = denial.
❌ 4. The wrong code was billed for a limited study
Repercussions include payer audits.
❌ 5. Repeat echo too soon
Must document why another echo was needed.
❌ 6. Lack of stored images
Medicare requires image archiving.
❌ 7. Missing physician interpretation
Billing 93306 requires a completed report.
Correct Billing Examples
Example 1 — Complete Echo with Doppler + Color
Clinic performs a full TTE
All structures evaluated
Doppler + color performed
Cardiologist interprets
→ Bill 93306
Example 2 — Patient Has Heart Murmur
Echo reveals:
- Mild MR
- Thickened leaflets
- Normal EF
→ Bill 93306 (complete echo)
Example 3 — Atypical Chest Pain
Echo needed to assess LV function and rule out structural abnormalities.
→ Bill 93306
Final Thoughts
CPT 93306 is the most commonly billed echocardiogram code and a core part of cardiology practice. Because this code covers a fully comprehensive echo—including Doppler and color flow—proper documentation and accurate code selection are crucial for avoiding denials and ensuring compliance.
If your practice needs help with echo documentation, CPT accuracy, payer rules, or reducing denials, Global Tech Billing LLC provides cardiology-focused billing support to ensure accurate and compliant reimbursement.
Frequently Asked Questions (FAQ)
1. Does CPT 93306 include Doppler?
Yes — it includes both spectral Doppler and color flow Doppler.
2. Can 93306 be billed with an E/M visit?
Yes — if separately identifiable.
Use modifier 25 on the E/M.
3. Does Medicare require prior authorization?
No.
4. Can you bill 93306 and 93308 on the same day?
Generally, no, unless:
- Clinical justification exists
- Different indications
- Different study types
5. Can 93306 be repeated within 6 months?
Yes, if medically necessary.
Document clearly.
6. Does 93306 require image storage?
Absolutely.
Lack of image retention leads to denials.
Strengthen remote monitoring workflows using our CPT 93228 Mobile Cardiac Telemetry Billing Guide covering setup, technician involvement, interpretation, and billing requirements.
7. Does CPT 93306 include contrast?
No. For contrast use, add Q9957/Q9950 or HCPCS codes as appropriate.
