Ventricular tachycardia electrical cardioversion


 * Associate Editor-in Chief: Avirup Guha, M.B.B.S.[mailto:avirup.guha@gmail.com]

Electrical Cardioversion / Defibrillation
It is usually possible to terminate a VT episode with a direct current shock across the heart. This is ideally synchronised to the patient's heartbeat. As it is quite uncomfortable, shocks should be delivered only to an unconscious or sedated patient. A patient with pulseless VT will be unconscious and treated as an emergency on a cardiac arrest protocol. Elective cardioversion is usually performed in controlled circumstances with anaesthetic and airway support.

The shock may be delivered to the outside of the chest using an external defibrillator, or internally to the heart by an implantable cardioverter-defibrillator (ICD) if one has previously been inserted.

An ICD may also be set to attempt to overdrive pace the ventricle. Pacing the ventricle at a rate faster than the underlying tachycardia can sometimes be effective in terminating the rhythm. If this fails after a short trial, the ICD will usually stop pacing, charge up and deliver a defibrillation grade shock.

Category : Electrophysiology