I4891 - Irregular heart rhythm (atrial fibrillation) without specific type identified

International Classification of Diseases

Last updated: 3/24/2026

What is a ICD-10 Code?

ICD-10 (International Classification of Diseases, 10th Revision) codes are used to classify and code all diagnoses, symptoms, and procedures recorded in association with hospital care. These codes provide a standardized way to track health conditions and their treatment outcomes.

Detailed Description

This code indicates atrial fibrillation, a condition where the heart's upper chambers (atria) beat irregularly and often rapidly. The 'unspecified' designation means the specific type or pattern of atrial fibrillation has not been determined or documented. Atrial fibrillation can cause symptoms like palpitations, shortness of breath, fatigue, or chest discomfort, though some people may have no symptoms at all.

Additional Information

This is a diagnosis code used for billing and medical record purposes. Treatment and prognosis vary significantly based on individual patient factors, underlying causes, and specific characteristics of the atrial fibrillation.

Category

Cardiovascular Disease

Medical Specialty

Cardiology

Expected Costs

Your actual cost will depend on your insurance coverage, provider location, and specific circumstances.

What to Expect After

  • Regular cardiac monitoring
  • Medication management
  • Lifestyle modifications
  • Possible anticoagulation therapy

Why Understanding This Code Matters

On Your Medical Bill

This code appears on your medical bills to identify the specific service, procedure, drug, or medical diagnosis you received. Understanding what it means helps you verify you're being charged correctly and know what to expect.

For Your Health

Knowing what this code represents helps you understand your treatment plan, ask better questions during appointments, and track your healthcare journey more effectively.

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