ICD-10-CM 2027
ICD-10 code for atrial depolarization
From the official ICD-10-CM alphabetic index entry “Depolarization, premature › atrial”. Page updated September 29, 2026.
About coding atrial depolarization
The ICD-10-CM code for atrial depolarization is I49.1 (Atrial premature depolarization).
Within I49 (other cardiac arrhythmias), I49.1 is specifically for atrial premature depolarization. Related codes cover ventricular fibrillation and flutter (I49.0), junctional premature depolarization (I49.2), ventricular premature depolarization (I49.3), other and unspecified premature depolarization (I49.4), sick sinus syndrome (I49.5), other specified cardiac arrhythmias (I49.8) and cardiac arrhythmia, unspecified (I49.9).
Code first cardiac arrhythmia complicating: abortion or ectopic or molar pregnancy (O00-O07, O08.8) and obstetric surgery and procedures (O75.4).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
Common questions about atrial depolarization ICD-10 codes
What is the ICD-10 code for atrial depolarization?
- I49.1 — Atrial premature depolarization.
Is I49.1 billable?
- Yes. I49.1 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can I49.1 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict I49.1 as a principal diagnosis.
Is I49.1 a CC or MCC?
- No. I49.1 is neither a CC nor an MCC under MS-DRG v44.0.