Is ICD-10-CM code I48 billable?

No, I48 (Atrial fibrillation and flutter) is a non-billable ICD-10-CM code. It must be coded to a more specific subcategory before it can be used for reimbursement.

What chapter does ICD-10-CM code I48 belong to?

I48 belongs to Chapter 9 of the ICD-10-CM tabular list: I00–I99 (Diseases of the Circulatory System).

I48Not billable, use a more specific code below

Atrial fibrillation and flutter

In Other forms of heart disease (I30-I5A), chapter 9: Diseases of the Circulatory System

9 billable codes under I48: 7 are a CC; all map to HCC 238 (Specified Heart Arrhythmias).A CC or MCC (major CC) is a secondary diagnosis that raises the MS-DRG payment. An HCC counts toward a Medicare Advantage patient's risk score.

Official coding guidelines

From the ICD-10-CM Official Guidelines for Coding and Reporting, FY 2027 (CMS and NCHS). Links open the PDF at the right page.

Covers hypertension with heart and kidney disease, coronary artery disease with angina, perioperative stroke, cerebrovascular sequelae, and acute myocardial infarction types and timing.

Hypertension (page 50)
Atherosclerotic Coronary Artery Disease and Angina (page 52)
Intraoperative and Postprocedural Cerebrovascular Accident (page 53)
Sequelae of Cerebrovascular Disease (page 53)
Acute myocardial infarction (AMI) (page 54)

Read Section I.C.9 (page 50)

All codes under I48

I48 can't be used on a claim. Pick a billable code below; grey headings group them.

I48 MS-DRGs

As the principal diagnosis, the billable codes under I48 group to MS-DRG 308, 309, 310, 791, or 793 (v44.0). Which one applies depends on procedures performed, secondary diagnoses (CC/MCC), and the patient's age and discharge status.

DRG 308 Cardiac Arrhythmia and Conduction Disorders with MCC (9 of 9 codes)
DRG 309 Cardiac Arrhythmia and Conduction Disorders with CC (9 of 9 codes)
DRG 310 Cardiac Arrhythmia and Conduction Disorders without CC/MCC (9 of 9 codes)
DRG 791 Prematurity with Major Problems (7 of 9 codes)
DRG 793 Full Term Neonate with Major Problems (7 of 9 codes)

About the condition

Plain-language background from MedlinePlus (National Library of Medicine), not coding guidance.

Arrhythmia

An arrhythmia is a problem with the rate or rhythm of your heartbeat. Your heart beats too quickly, too slowly, or with an irregular pattern. Changes in the electrical signals that control your heartbeat cause arrhythmias.

Atrial Fibrillation

Atrial fibrillation, also known as AFib or AF, is one of the most common types of arrhythmias. Arrhythmias are problems with the rate or rhythm of your heartbeat. They can cause your heart to beat too slowly, too fast, or in an irregular way.

Code history

Valid since FY2016, when ICD-10-CM took effect on October 1, 2015. No changes since.