ICD-10 Code I48.0 – Paroxysmal atrial fibrillation (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I48.0 – Paroxysmal atrial fibrillation
What it is
Paroxysmal atrial fibrillation is an intermittent heart rhythm disorder that starts and stops on its own. The atria beat irregularly during episodes, but the rhythm returns to normal without ongoing intervention.
Clinical signs
Patients may report palpitations, shortness of breath, fatigue, chest discomfort, or dizziness. Clinical features vary; refer to documentation, and use ECG or monitor findings when the record identifies paroxysmal atrial fibrillation.
When to use this code
Use I48.0 when the provider documents atrial fibrillation that occurs in episodes and spontaneously resolves. It also applies when the note clearly states paroxysmal AF, even if the patient is asymptomatic at the visit. Check documentation if the rhythm type is not specified.
Do not use for
Do not use this code for chronic, persistent, or permanent atrial fibrillation unless the record specifically says paroxysmal. If the diagnosis is uncertain or another arrhythmia is documented, check documentation.
Coding tip
Code from the provider’s stated AF type; episode frequency or symptom severity does not change I48.0.