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  2. ICD-10-CM Codes List
  3. I00–I99
  4. I30-I5A
  5. Atrial fibrillation and flutter (I48)

Atrial fibrillation and flutter (I48)

ICD-10 codes I48 and its subcategories are used to diagnose and document different types of atrial fibrillation and atrial flutter, which are heart rhythm disorders involving rapid and irregular beating of the atria. These codes differentiate specific forms such as paroxysmal, persistent, longstanding persistent, chronic, permanent atrial fibrillation, and typical or atypical atrial flutter.

These codes help medical coders identify conditions like paroxysmal atrial fibrillation (I48.0), also called "atrial fibrillation with rapid ventricular response" or "non-rheumatic atrial fibrillation." Persistent forms include persistent atrial fibrillation (I48.1) and its longstanding variant (I48.11). Chronic and permanent types are coded as I48.20 and I48.21, respectively. The section also covers atrial flutter, with typical (I48.3) and atypical (I48.4) forms, distinguished by their EKG patterns. Unspecified categories (I48.9, I48.91, I48.92) allow documentation when precise subtypes aren't determined. The codes are essential for diagnosing these arrhythmias, tracking their progression, and guiding treatment decisions in cardiac care settings.

Clinical Terms

The following clinical terms provide additional context, helping users better understand the clinical background and common associations for each diagnosis listed in this section. Including related terms alongside ICD-10-CM codes supports coders, billers, and healthcare professionals in improving accuracy, enhancing documentation, and facilitating research or patient education.

Atrial Fibrillation

Abnormal cardiac rhythm that is characterized by rapid, uncoordinated firing of electrical impulses in the upper chambers of the heart (HEART ATRIA). In such case, blood cannot be effectively pumped into the lower chambers of the heart (HEART VENTRICLES). It is caused by abnormal impulse generation.

Atrial Flutter

Rapid, irregular atrial contractions caused by a block of electrical impulse conduction in the right atrium and a reentrant wave front traveling up the inter-atrial septum and down the right atrial free wall or vice versa. Unlike ATRIAL FIBRILLATION which is caused by abnormal impulse generation, typical atrial flutter is caused by abnormal impulse conduction. As in atrial fibrillation, patients with atrial flutter cannot effectively pump blood into the lower chambers of the heart (HEART VENTRICLES).