ICD-10 Code I48.3 – Typical atrial flutter (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I48.3 – Typical atrial flutter
What it is
Use this code for typical atrial flutter, a supraventricular arrhythmia caused by a reentry circuit in the right atrium. It is a distinct atrial rhythm disorder and is not the same as atrial fibrillation.
Clinical signs
Typical findings include a regular rapid atrial rhythm, often with sawtooth flutter waves on ECG. Clinical features vary; refer to documentation for whether the rhythm is typical, persistent, or paroxysmal.
When to use this code
Assign I48.3 when the provider documents typical atrial flutter as the diagnosis, including episodes noted on ECG or rhythm monitoring. Use it for confirmed atrial flutter even if the patient is asymptomatic or the finding is incidental. Check documentation if the record only says “atrial arrhythmia” or “flutter” without specifying typical atrial flutter.
Do not use for
Do not use this code for atrial fibrillation, unspecified atrial flutter, or other supraventricular tachycardias. If the documentation does not identify the flutter as typical, check documentation.
Coding tip
Code only when the provider clearly identifies typical atrial flutter; otherwise, query for specificity.