I48.9
Unspecified atrial fibrillation and atrial flutter
Non-billable headerNot valid on its own. Use one of the more specific codes under it.
I48.9 is a non-billable ICD-10-CM code header for unspecified atrial fibrillation and atrial flutter. Report a more specific code from it instead. It is part of the FY2027 code set, effective October 1, 2026. The more specific codes under it are I48.91 Unspecified atrial fibrillation and I48.92 Unspecified atrial flutter. Its coding notes include 10 Excludes2 entries.
Excludes2
Not included here. Both codes may be reported if the patient has both conditions.
Also from chapter/block level (10 notes)
Inherited from Chapter 9 Diseases of the circulatory system
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional and metabolic diseases (E00-E88)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
- systemic connective tissue disorders (M30-M36)
- transient cerebral ischemic attacks and related syndromes (G45.-)