T58.8X1A — Toxic effect of carbon monoxide from other source, accidental (unintentional), initial encounter
ICD-10-CM
Prior Authorization
No Prior Auth Required
Code is covered without prior authorization (high confidence)
Documentation Required
- This article provides billing/coding guidelines that complement Local Coverage Determination L34417 for CT of the head; consult LCD L34417 for specific coverage, coding, and documentation requirements.
- When a limited or follow-up echocardiogram is performed, document the targeted cardiac problem/region and bill using the appropriate CPT code (93308 or 93321).
- If the study is a screening exam, document and bill with the appropriate screening ICD-10 code; document any abnormal findings and use the resulting diagnosis for subsequent billing when applicable.
- Document use of ultrasound contrast enhancement and its supplies separately when billed, and do not submit separate claims for diagnostic injection services integral to the contrast procedure.
Key Coverage Criteria
- Follow-up or limited transthoracic echocardiography performed to evaluate a single specified cardiac problem or region must be billed with CPT 93308.
- Limited Doppler/follow-up echocardiographic studies (for targeted velocity or gradient assessment) should be billed with CPT 93321 (e.g., tricuspid regurgitant velocity to estimate pulmonary artery systolic pressure or sequential transmitral velocity in mitral stenosis).
- Echocardiograms performed as part of the CAMZYOS REMS program are covered when billed with modifier KX and all REMS program requirements are met for patients with NYHA Class II–III obstructive hypertrophic cardiomyopathy (I42.1).
- An ECG is covered when the result is relevant to the management, diagnosis, or treatment of the patient.
- A separate ECG on the same day as a cardiac stress test is payable only when it provides additional clinically necessary information beyond the stress test (e.g., to rule out acute myocardial infarction prior to performing the stress test).
- Rhythm ECGs are covered when used to evaluate signs or symptoms suggesting a cardiac rhythm disorder.
11 Active Policies
L35434 — Oximetry Services
J12
A57205 — Billing and Coding: Oximetry Services
J12
A56625 — Billing and Coding: Echocardiography
A57306 — Billing and Coding: Transthoracic Echocardiography (TTE)
A57326 — Billing and Coding: Electrocardiograms
Related Codes
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