EKG Dictionary
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Junctional & ventricular rhythms

Ventricular fibrillation

Also calledVF · V-fib · V fib · VFib · VF arrest

Definition

Rapid, grossly irregular, chaotic ventricular electrical activity, with waves that vary continuously in shape and amplitude, at a ventricular rate usually above 300 per minute. It is one of the rhythms of cardiac arrest, and it may begin as ventricular tachycardia or torsades de pointes that degenerates into ventricular fibrillation.

Sources

  1. Al-Khatib SM, Stevenson WG, Ackerman MJ, et al. 2017 AHA/ACC/HRS guideline for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death: executive summary. J Am Coll Cardiol. 2018;72(14):1677-1749. doi.org/10.1016/j.jacc.2017.10.053
  2. Samesima N, God EG, Kruse JCL, et al. Brazilian Society of Cardiology guidelines on the analysis and issuance of electrocardiographic reports - 2022. Arq Bras Cardiol. 2022;119(4):638-680. doi.org/10.36660/abc.20220623

Last reviewed 2 October 2026. Every definition in the EKG Dictionary cites the guideline, consensus statement or original paper it comes from.

More in Junctional & ventricular rhythms

Accelerated idioventricular rhythm (AIVR) Accelerated junctional rhythm Coupling interval Idioventricular rhythm Junctional ectopic tachycardia (JET) Junctional escape rhythm Junctional rhythm Junctional tachycardia Monomorphic VT Polymorphic VT Premature ventricular contraction (PVC) R-on-T phenomenon Retrograde P wave Torsades de pointes Ventricular bigeminy Ventricular couplet Ventricular tachycardia (VT) Ventricular trigeminy

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