ICD-10 Code I49.01 – Ventricular fibrillation (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I49.01 – Ventricular fibrillation
What it is
Ventricular fibrillation is a dangerous heart rhythm where the ventricles quiver instead of pumping blood effectively. It causes immediate loss of cardiac output and is a medical emergency.
Clinical signs
Typical findings include sudden collapse, unresponsiveness, and absence of a palpable pulse. ECG shows chaotic, disorganized ventricular activity with no effective QRS complexes.
When to use this code
Use I49.01 when documentation confirms ventricular fibrillation as the diagnosed rhythm, whether initial or recurrent. It applies when the record identifies VF on monitor, ECG, or defibrillation documentation. Check documentation if the rhythm is described only as cardiac arrest or asystole.
Do not use for
Do not use this code for ventricular tachycardia, atrial fibrillation, or nonspecific cardiac arrest without VF documented. If the note does not clearly state ventricular fibrillation, check documentation.
Coding tip
Code the rhythm exactly as documented and confirm whether VF is the principal diagnosis or a complication.