V Fib (Ventricular Fibrillation)

This page provides a definition followed by an synopsis of EKG features. Links to our practice drills, quizzes, lessons and interactive guides can be found below.

V Fib Definition

V Fib (Ventricular fibrillation) is an emergency that requires immediate medical attention. It is a frequent cause of sudden cardiac death. When it occurs, the coordinated contraction of the ventricles is replaced rapid, chaotic electrical signals. As a result, the heart cannot pump blood.

V-Fib Treatment

Ventricular fibrillation is a life threatening emergency and must be treated immediately by qualified medical professionals.

Healthcare professionals should follow facility protocols. For more information, review the ACLS algorithms.

Treatment may involve CPR (chest compressions) and use of a defibrillator.

Longer term treatment options include medicines to control heart function and implantable defibrillators (ICD).


The following table summarizes the key features of a V Fib EKG rhythm strip.

Rhythm Highly irregular
Rate Unmeasurable
P Wave Absent
PR Interval Not measurable
QRS None
Notes EKG tracings is a wavy line
V-Fib ekg strip

EKG Training

A good starting point for learning about V-Fib and other types of EKG interpretation is our EKG Basics training course. The course provides training on the key features of an EKG tracing. These features include observing P-wave forms, measurement of EKG intervals and segments, assessment of rhythm, calculating heart rate, and the evaluation of other relevant wave segments. The arrhythmia practice drills allow students to build skills interactively.

EKG Basics

EKG Practice Drills

The heart arrhythmia practice drills provide a test EKG tracing and users are asked to identify the type of arrhythmia. Many of these drills include tachycardia EKG tracings. Each answer is immediately evaluated and the correct classification of the EKG tracing is provided, along with a detailed explanation. A directory of arrhythmias is also provided.

Arrhythmia Practice Drills

ECG Quiz

The quiz is structured like a classroom exam. The quiz present twenty EKGs. Users answer each question and at the end of the quiz, a fully graded report is provided. This graded report provides scoring as well as the correct answer to each question. Top scores and mean scores are also provided. This quiz draws its questions from a library of over 300 EKGs, allowing users to take the quiz multiple times.

ECG Quiz

ECG Monitor Challenge (beta version)

Try the beta version of our ECG monitor challenge. This quiz uses a simulated patient monitor with moving waveform instead of a paper tracing. As with the quiz described above, twenty questions are presented, then a graded report is available.

ECG Monitor Challenge

External References