Implantable cardioverter-defibrillator

An implantable electronic device that monitors heart rhythm and treats dangerous rapid arrhythmias with electrical pacing or shocks.

Ventricular tachycardia: A rapid rhythm arising in the ventricles that can impair circulation or progress to ventricular fibrillation. This is a major rhythm an ICD detects and may treat with pacing or a shock.
Sudden cardiac death: An unexpected death caused by loss of effective heart function, often following a dangerous arrhythmia. Preventing arrhythmic sudden death is the central purpose of ICD therapy.
Heart: A muscular organ that circulates blood through the pulmonary and systemic circulations. The ICD’s leads and electrical therapies act on the heart’s rhythm and contraction.
External defibrillation: Delivery of a defibrillation shock through electrodes placed on the outside of the body. Unlike an ICD’s automatic internal therapy, external defibrillation is administered from outside the body.
Ventricular fibrillation: Disorganized ventricular electrical activity that prevents effective pumping of blood. An ICD can terminate this lethal rhythm with a high-energy shock.
Primary prevention: Intervention intended to prevent a first occurrence of a disease or event. An ICD may be implanted before any sustained ventricular arrhythmia in people at high predicted risk.
Cardiac conduction system: Specialized cardiac tissue that generates and conducts electrical impulses coordinating heartbeats. Its electrical pathways produce the signals an ICD monitors and can influence with pacing.
Single-chamber implantable cardioverter-defibrillator: An ICD with a lead that senses and stimulates one heart chamber, typically the right ventricle. It is a simpler configuration than systems with additional atrial or ventricular leads.
Antitachycardia pacing: A sequence of rapid pacing pulses used to interrupt certain fast heart rhythms. Many ICDs try this less painful treatment before delivering a shock for ventricular tachycardia.
Secondary prevention: Intervention intended to prevent recurrence after a disease event has already occurred. An ICD often prevents recurrence after a survivor’s life-threatening ventricular arrhythmia.

Linked from 14 pages