ICD-10 Code I45.1 – Other and unspecified right bundle-branch block (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I45.1 – Other and unspecified right bundle-branch block
What it is
I45.1 identifies a conduction abnormality in the right bundle branch of the heart’s electrical system. It means the impulse travels abnormally through the right ventricle, and the documentation does not specify a more exact bundle-branch block type.
Clinical signs
Clinical features vary; refer to documentation. This finding is often identified on electrocardiogram, with patterns consistent with right bundle-branch block and no further subtype specified.
When to use this code
Use I45.1 when the provider documents other or unspecified right bundle-branch block, or when the ECG report states RBBB without enough detail for a more specific code. Code the documented conduction defect, not a symptom alone. Check documentation if the record suggests a different conduction disorder.
Do not use for
Do not use this code for left bundle-branch block, bifascicular block, or nonspecific ECG changes without a documented right bundle-branch block. If the chart names a different arrhythmia or conduction defect, choose the more accurate code.
Coding tip
Match the code to the exact ECG or provider wording, and avoid assuming “RBBB” means unspecified if a more specific diagnosis is documented.