G658 – Professional component - 36 to 59 hours recording
OHIP Diagnostic & Therapeutic Procedures Code — DIAGNOSTIC AND THERAPEUTIC PROCEDURES · Schedule of Benefits
The professional component for a Level 1 continuous ECG monitoring service. This service is for recordings lasting 36 to 59 hours. Level 1 requires a device capable of recording three or more simultaneous channels and the acquisition of a continuous ambulatory electrocardiographic recording of all beats. The device must also have the ability to analyze and manually review all parts of the recording, and to produce graphical and quantitative reports of relevant parameters and diagnostic quality tracings for visual review, including post-hoc review of any portion of the recording to enable diagnostic rhythm analysis. Must include a patient diary and event marker capability to enable symptom-rhythm correlation. The fee covers the physician's interpretation and written report. See for details. A professional component is a class of service listed in the Schedule headed by a column listed 'P' or with 'professional component' listed opposite the service. See .
When to Use
- Use G658 when the total duration of the continuous ambulatory ECG recording is strictly between 36 and 59 hours, inclusive.
- Use this code for the physician's professional interpretation of a Level 1 (3+ channel) Holter monitor, ensuring the patient diary and event markers were utilized for symptom correlation.
Common Pitfalls
- Billing G658 for recordings lasting less than 36 hours (use G657) or 60 hours or more (use G659) will result in automatic rejection or audit recovery.
- Attempting to bill G658 without the corresponding technical components (G682 for recording and G683 for scanning) is a common error; all three must be present for a complete service claim.
- Failure to maintain the patient diary as part of the medical record is a frequent audit failure, as the code explicitly requires symptom-rhythm correlation.
Billing Tips
- Always verify the exact start and end times of the recording against the device log before submitting, as the duration determines the specific code in the G657-G659 series.
- Ensure the written report explicitly references the review of the patient diary and the correlation of symptoms to rhythm events to meet the 'diagnostic rhythm analysis' requirement.
Effective: April 1, 2025
J. Diagnostic and Therapeutic Procedures
DIAGNOSTIC AND THERAPEUTIC PROCEDURES
Diagnostic
Diagnostic and Therapeutic Procedures
Maximum one professional component, one technical recording component and one technical scanning component per patient, per recording.
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