Atrial fibrillation and flutter (I48) ICD-10-CM
The I48 code range covers atrial fibrillation and flutter with 13 ICD-10-CM diagnosis codes. 9 of them are billable and valid for claim submission in fiscal year 2027, and the category headers group them but cannot themselves be billed.
Codes in the I48 Range 13 codes · 9 billable
- I48 Atrial fibrillation and flutterNon-billable
- I48.0 Paroxysmal atrial fibrillation
- I48.1 Persistent atrial fibrillationNon-billable
- I48.11 Longstanding persistent atrial fibrillation
- I48.19 Other persistent atrial fibrillation
- I48.2 Chronic atrial fibrillationNon-billable
- I48.20 Chronic atrial fibrillation, unspecified
- I48.21 Permanent atrial fibrillation
- I48.3 Typical atrial flutter
- I48.4 Atypical atrial flutter
- I48.9 Unspecified atrial fibrillation and atrial flutterNon-billable
- I48.91 Unspecified atrial fibrillation
- I48.92 Unspecified atrial flutter
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the I48 range.
Chronic Atrial Fibrillation
A disorder characterized by a long standing and persistent uncoordinated atrial myocardium activation due to multiple reentry circuits with consequent deterioration of atrial mechanical function. Instead of intermittently contracting, the atria quiver continuously in a chaotic pattern, causing a totally irregular, often tachycardia ventricular rate. On the ECG it is characterized by the replacement of consistent P waves by rapid oscillations or fibrillatory waves that vary in size, shape, and timing, associated with an irregular, frequently rapid ventricular response when atrioventricular conduction is intact.
Paroxysmal Atrial Fibrillation
A disorder characterized by an electrocardiographic finding of episodic atrial fibrillation with abrupt onset and termination.
Persistent Atrial Fibrillation by ECG Finding
An electrocardiographic tracing demonstrating atrial fibrillation that is present during the entire recording.
About the I48 Code Range
Atrial fibrillation and atrial flutter sit among other forms of heart disease. Their subdivisions distinguish the named forms of each condition.
For atrial fibrillation, I48.0 is paroxysmal. Persistent atrial fibrillation splits into longstanding persistent and other persistent forms under I48.1. Chronic atrial fibrillation splits into unspecified chronic and permanent forms under I48.2.
Atrial flutter is divided into typical I48.3 and atypical I48.4. The unspecified branch I48.9 separates unspecified atrial fibrillation from unspecified atrial flutter.
Questions About This Page
How many billable codes are in the I48 range?
Of the 13 codes in this range, 9 are billable and valid for claim submission from October 1, 2026 through September 30, 2027. Category header codes group them but cannot be reported on claims.
What does the I48 range classify?
The range classifies atrial fibrillation and flutter. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2027 ICD-10-CM Tabular List and order file, effective October 1, 2026 through September 30, 2027.
