Automated external defibrillator

An automated external defibrillator or automatic electronic defibrillator (AED) is a portable electronic device that automatically diagnoses the life-threatening cardiac arrhythmias of ventricular fibrillation (VF) and pulseless ventricular tachycardia, and is able to treat them through defibrillation, the application of electricity which stops the arrhythmia, allowing the heart to re-establish an effective rhythm. With simple audio and visual commands, AEDs are designed to be simple to use for the layperson, and the use of AEDs is taught in many first aid, certified first responder, and basic life support (BLS) level cardiopulmonary resuscitation (CPR) classes. The portable version of the defibrillator was invented in the mid-1960s by Frank Pantridge in Belfast, Northern Ireland and the first automatic, public-use defibrillator was produced by the Cardiac Resuscitation Company in the late 1970s. The unit was launched under the name Heart-Aid. An automated external defibrillator is used in cases of life-threatening cardiac arrhythmias which lead to sudden cardiac arrest, which is not the same as a heart attack. The rhythms that the device will treat are usually limited to: Pulseless Ventricular tachycardia (shortened to VT or V-Tach) Ventricular fibrillation (shortened to VF or V-Fib) In each of these two types of shockable cardiac arrhythmia, the heart is electrically active, but in a dysfunctional pattern that does not allow it to pump and circulate blood. In ventricular tachycardia, the heart beats too fast to effectively pump blood. Ultimately, ventricular tachycardia leads to ventricular fibrillation. In ventricular fibrillation, the electrical activity of the heart becomes chaotic, preventing the ventricle from effectively pumping blood. The fibrillation in the heart decreases over time, and will eventually reach asystole. AEDs, like all defibrillators, are not designed to shock asystole ('flat line' patterns) as this will not have a positive clinical outcome.