Question

How does cardioversion differ from defibrillation?

Answer 1

Defibrillation - is the treatment for immediately life-threatening arrhythmias with which the patient does not have a pulse, ie ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT).Cardioversion - is any process that aims to convert an arrhythmia back to sinus rhythm. Electrical cardioversion is used when the patient has a pulse but is either unstable, or chemical cardioversion has failed or is unlikely to be successful. These scenarios may be associated with chest pain, pulmonary oedema, syncope or hypotension. It is also used in less urgent cases - eg, atrial fibrillation (AF) - to try to revert the rhythm back to sinus.

The aim in both is to deliver electrical energy to the heart to stun the heart momentarily and thus allow a normal sinus rhythm to kick in via the heart's normal pacemaker, ie the sinoatrial node.