How does a defibrillator function?

Electrical system. A defibrillator causes all myocardial (heart) cells to become depolarized at the same time. This extinguishes the abnormal arrhythmia, and allows the natural cardiac pacemaker to kick back in. This requires a large electrical current, to make sure all myocardial cells get activated at the same time.
Defibirllator. The defibibrillator is a mini computer with a sensing circuit and a shock circuit. If the device senses a life threatening arrhythmia for a certain time period, then the device charges and will shock the patient out of the life threatening arrhythmia. The defibrillator is programmed by the electrophysiologist based on the studies done prior to implant and then after implant it is tested.

Related Questions

How does an internal defibrillator function?

Shocks heart. It monitors the heart rhythm looking for certain dangerous types of rapid heart rhythm. If it detects such a rhythm, it delivers a shock to the heart which hopefully restores a regular rhythm. It also has the capacity to pace the heart if the beating is too slow. Read more...
Monitor. It monitor abnormally rapid atrial and ventricular rate with certain parameter and it will deliver a shock if it detects rapid ventricular tachycardia or fibrillation. Read more...

How does an implantable cardioverter defibrillator function?

Detection. It detects fast heart beats above a threshold set by the cardiologist and programmed into the defibrillator and delivers a shock or atp - pacemaker override, depending on the heart rate. It will deliver subsequent shocks depending on the heart rate it detects. Read more...
Defibrillators. The device has an antenna that monitors the electrical activity of the heart. If the recorded parameters fit those of ventricular tachycardia or ventricular fibrillation, the device will charge its capacitor and deliver programmed shocks to try and return the rhythm to normal. It is a computer and programmed to do its functions. They are very effective but not perfect. Read more...