ICD-10 Code I44.0 – Atrioventricular block, first degree (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I44.0 – Atrioventricular block, first degree
What it is
First-degree atrioventricular block is a delay in electrical conduction between the atria and ventricles. On ECG, the PR interval is prolonged, but every atrial impulse still reaches the ventricles.
Clinical signs
Many patients have no symptoms, and the finding is often incidental on ECG. Clinical features vary; refer to documentation for any associated rhythm findings or symptoms such as palpitations or dizziness.
When to use this code
Use I44.0 when the provider documents first-degree AV block, PR prolongation, or atrioventricular conduction delay as the diagnosis. Apply it when the record clearly identifies the conduction defect, even if it was found during routine testing. If the note is unclear, check documentation.
Do not use for
Do not use this code for second- or third-degree AV block, bundle branch block, or nonspecific ECG abnormalities. If the record only says “abnormal ECG,” check documentation before coding.
Coding tip
Code the documented conduction disorder exactly as stated and avoid upgrading severity without provider support.