Defibrillation is a treatment for life-threatening cardiac dysrhythmias, specifically ventricular fibrillation and non-perfusing ventricular tachycardia.
Cardiac arrhythmia, also known as cardiac dysrhythmia or irregular heartbeat, is a group of conditions in which the heartbeat is irregular, too fast, or too slow.
Ventricular tachycardia is a type of regular and fast heart rate that arises from improper electrical activity in the ventricles of the heart.
Ventricular fibrillation is when the heart quivers instead of pumping due to disorganized electrical activity in the ventricles.
Cardioversion of Atrial Flutter by Larry Mellick
A defibrillator delivers a dose of electric current to the heart.
The heart is a muscular organ in humans and other animals, which pumps blood through the blood vessels of the circulatory system.
How to perform Cardioversion and Defibrillation by Pat Vaughn
The electrical shock does not have to be timed with the heart's intrinsic cardiac cycle.
The cardiac cycle refers to the sequence of mechanical and electrical events that repeats with every heartbeat.
This depolarizes a large amount of the heart muscle, ending the dysrhythmia.
Subsequently, the body's natural pacemaker in the sinoatrial node of the heart is able to re-establish normal sinus rhythm.
A sinus rhythm is any cardiac rhythm where depolarisation of the cardiac muscle begins at the sinus node.
The sinoatrial node is a group of cells located in the wall of the right atrium of the heart.
In contrast to defibrillation, synchronized electrical cardioversion is an electrical shock delivered in synchrony to the cardiac cycle.
Cardioversion is a medical procedure by which an abnormally fast heart rate or other cardiac arrhythmia is converted to a normal rhythm using electricity or drugs.
Although the person may still be critically ill, cardioversion normally aims to end poorly perfusing cardiac dysrhythmias, such as supraventricular tachycardia.
Defibrillators can be external, transvenous, or implanted, depending on the type of device used or needed.
Some external units, known as automated external defibrillators, automate the diagnosis of treatable rhythms, meaning that lay responders or bystanders are able to use them successfully with little or no training.
An automated external defibrillator is a portable electronic device that automatically diagnoses the life-threatening cardiac arrhythmias of ventricular fibrillation and ventricular tachycardia in a patient, and is able to treat them through defibrillation, the application of electrical therapy which stops the arrhythmia, allowing the heart to reestablish an effective rhythm.