Implantable Cardioverter Defibrillator
An implantable cardioverter defibrillator (ICD) is an electronic device that is implanted under the skin, and is used to detect an abnormal heartbeat. An ICD is often implanted in individuals with irregular heartbeats or heart arrhythmias. This device uses electrical impulses to control dangerous arrhythmias that may lead to heart attack or sudden cardiac arrest. If an abnormal heartbeat is detected, the ICD will deliver an internal electric shock to the heart, restoring a normal heart beat as needed.
An implantable cardioverter defibrillator use electrical pulses or shocks, to treat life-threatening arrhythmias that occur in the ventricles, or lower chambers of the heart. When ventricular arrhythmias occur, the heart cannot properly pump the blood. This may cause a person to lose consciousness within seconds and die within minutes if not treated. To prevent these dangerous results, heart arrhythmias must be treated right away with an electric shock to the heart, a treatment known as defibrillation. Individuals at risk for life-threatening ventricular arrhythmia may include people who have:
- Congenital heart disease
- Brugada syndrome
- Existing ventricular arrhythmia
- Experienced cardiac arrest
Individuals who have had a previous heart attack are at risk for ventricular arrhythmia and may be candidates for an implantable cardioverter defibrillator.
How An ICD Works
An ICD is a small, battery-operated device that is implanted under the skin, below the left collarbone, to help maintain a regular heartbeat. The ICD sends electronic signals to the heart to help it pump properly when needed. The ICD consists of two flexible parts: the lead and the pulse generator. The lead monitors and treats the heart, while the generator contains a battery and tiny computer. When a very fast or abnormal heart beat is detected, the ICD sends energy to the heart to shock it and help it return to a normal rhythm.
The ICD Implantation Procedure
A cardioverter defibrillator is surgically implanted and the procedure is performed in a hospital. A small incision is made under the collarbone, and the lead is placed in a vein and led to the heart chamber, while the generator remains attached to it and is placed under the skin of the upper chest. After the ICD is implanted, the doctor programs it to treat the individual’s specific heart rhythm problem. Although rare, complications of an ICD implant may include infection, bleeding, damage to veins or puncture of the heart or lung.
Patients should avoid strong electric or magnetic fields after the implantation of the cardioverter defibrillator. An ICD battery lasts an average of 7 to 10 years and should be checked regularly and replaced by a doctor when necessary.