All codes
E661
E661 – Endocardial E.P.S. mapping
OHIP Surgical Assists Code — CARDIOVASCULAR SURGICAL PROCEDURES · Schedule of Benefits
E661 is an add-on surgical service for endocardial electrophysiologic study (EPS) mapping. It is performed in conjunction with a primary cardiotomy procedure to map the heart's electrical pathways from within the endocardium. This service is claimed in addition to the fee for the main surgical procedure.
When to Use
- Use E661 when performing endocardial mapping during a primary cardiac surgical procedure that is not specifically defined as an ablation or division of an accessory pathway.
- Use this code when mapping is required as a diagnostic adjunct during open-heart surgery where the mapping itself is a distinct, non-included procedural step.
Common Pitfalls
- Do not claim E661 alongside R710 or R711, as the Ministry considers mapping an inherent component of these specific ablation and division procedures.
- Avoid billing E661 for mapping services that are already bundled into the primary surgical fee code, as this will trigger an automatic rejection for unbundling.
Billing Tips
- Ensure the primary surgical procedure is clearly documented to justify the necessity of the additional mapping service as a separate, billable entity.
- Apply relevant age premiums (e.g., for patients under 16) to the E661 fee when the primary surgical procedure also qualifies for these modifiers.
Ready to bill this code?
SnapBill makes OHIP billing simple — auto-filled codes, validation, and batch submission.