Diseases of the Circulatory System
ICD-10 Code: I48.91
Unspecified Atrial Fibrillation
Atrial fibrillation without specification of type (paroxysmal, persistent, permanent).
Clinical Information
AFib affects 2-6 million Americans. Irregular atrial rhythm leading to irregular ventricular response. Used when AFib type not specified. Increases stroke risk; most patients need anticoagulation.
Coding Guidelines
- 1Use when 'atrial fibrillation' documented without specifying type
- 2If paroxysmal, use I48.0; persistent I48.1; permanent I48.21
- 3Use additional code for anticoagulation if applicable
Common Uses
- Primary care AFib management
- Cardiology follow-up for rate control
Related ICD-10 Codes
I48.0Paroxysmal atrial fibrillation
I48.1Persistent atrial fibrillation
Documentation Requirements
- Document 'atrial fibrillation' or 'AFib'
- Specify type if known (paroxysmal/persistent/permanent)
- Anticoagulation status
Real-World Coding Examples
75-year-old with AFib on apixaban and metoprolol. Rate controlled. Diagnosis: Unspecified atrial fibrillation (I48.91), Long-term use of anticoagulants (Z79.01)
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