What is an Implantable Cardioverter Defibrillator (ICD)?

• An ICD is a small, battery-powered device placed under the skin below the collarbone
• Thin wires connect the device to the heart
• It continuously monitors heart rhythm
• If a dangerous abnormal rhythm is detected, it delivers an electric shock to restore normal heartbeat

Types of ICD

Traditional ICD

• Placed in the chest under the skin
• Wires (leads) are connected directly to the heart

Subcutaneous ICD (S-ICD)

• Placed under the skin on the side of the chest below the armpit
• A sensor (electrode) runs along the breastbone
• Does not connect directly to the heart
• Larger than a traditional ICD

Why Might I Need an ICD?

• Ventricular arrhythmia
• Heart attack
• Survival after sudden cardiac arrest
• Long QT syndrome
• Brugada syndrome
• Congenital heart disease
• Cardiac sarcoidosis
• Other conditions increasing risk of sudden cardiac arrest

Who is a Candidate for ICD?

An ICD may be used when there is a life-threatening rhythm problem without correctable causes, such as heart attack, reduced blood flow to heart muscle, electrolyte imbalance, or drug toxicity.

How is an ICD Implanted?

• A small pulse generator (battery device) is placed under the skin of the chest, usually below the collarbone
• In infants, it may be placed in the abdomen
• Leads (wires) are guided through blood vessels to the heart
• No open-heart surgery is needed

Before the Procedure

• You may be asked not to eat or drink for a few hours
• Inform your doctor about all medicines you take
• Ask which medicines to continue or stop
• Arrange someone to drive you home and help during recovery

During the Procedure

• An IV line is placed in your arm or hand
• You may receive sedative medicine or general anaesthesia
• Heart rhythm is monitored using sticky electrode patches
• A small cut is made in the chest area
• Wires are guided through a blood vessel to the heart
• The device is placed under the skin below the collarbone
• The procedure takes a few hours

Testing the ICD

• The device is tested after placement
• It is programmed for your heart rhythm needs
• Low-energy pacing: mild fluttering sensation or no feeling
• High-energy shock: brief painful shock in serious rhythm problems

If 3 or more shocks occur in a short time, it is an emergency and medical help should be sought immediately.

After the Procedure

• Most patients go home the next day
• The implant site may be sore or swollen for a few days or weeks
• Pain medicines may be given (avoid aspirin and ibuprofen unless advised)

Activity Restrictions

• Avoid raising the left arm above the shoulder for about 8 weeks
• Avoid heavy lifting and strenuous exercise for about 4 weeks
• Avoid sports like golf, tennis, swimming, bowling, and vacuuming initially
• Contact sports should be avoided to prevent device damage

Risks of ICD Surgery

• Infection at the implant site
• Swelling, bleeding, or bruising
• Blood vessel damage from ICD wires
• Bleeding around the heart (can be life-threatening)
• Leaking of blood through the heart valve where the lead is placed
• Collapsed lung
• Movement of device or wires
• Rare heart injury (cardiac perforation)

How Does an ICD Work?

• Monitors heart rhythm 24 hours a day
• Detects abnormal heart rhythms automatically
• Acts as a pacemaker if the heart beats too slowly
• Delivers a shock if the heartbeat is too fast or irregular
• Provides backup pacing when needed
• Stores heart rhythm data for doctors to review

Living With an ICD

• Be aware of devices with strong magnetic fields
• These may interfere with ICD function
• Risk depends on closeness and duration of exposure
• Ask your healthcare team which devices or machines to avoid

Myths vs Facts

Frequently Asked Questions