(Implantable Cardioverter Defibrillators [ICD]; Automatic Implantable Cardioverter Defibrillator [AICD])
An implantable cardioverter defibrillator (ICD) is a small, battery-operated device that monitors the heart’s rhythm and provides appropriate treatment. Most ICDs have both pacemaker and defibrillator functions. If the heart beats too slowly, the ICD can help the heart beat at a normal pace. If the heart begins to beat in a disorganized way, the device provides a shock to restore a normal rhythm. ICD implantation is the surgical insertion of an ICD.
Implanted Cardioverter Defibrillator
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Reasons for Procedure
Certain heart rhythms are extremely dangerous and can lead to sudden cardiac death or cardiac arrest. Some irregular rhythms that may require an ICD implant include:
- Bradycardia—heart beating too slowly
- Ventricular tachycardia—heart beating too rapidly
- Ventricular fibrillation—heart muscle not pumping, but just quivering
ICDs are implanted in patients who:
- Have had one or more episodes of serious irregular heart rhythms
- Have had a heart attack and are at high risk for arrhythmias
- Have a high risk of dangerous arrhythmias
- Have a weakened heart muscle
- Have a high likelihood of developing an arrhythmia
- Have the condition known as hypertrophic cardiomyopathy, which is an enlarged heart muscle that does not function properly
If you are planning to have a defibrillator implanted, your doctor will review a list of possible complications, which may include:
- Damage to the heart or lungs
- Damage to blood vessels
- Inappropriate shocks or device malfunction
Some factors that may increase the risk of complications include:
What to Expect
Prior to Procedure
The following test may be conducted prior to your procedure:
- Blood tests
- Chest x-ray—a test that uses radiation to take a picture of structures inside the body
- Electrocardiogram (ECG), implantable loop recorders (ILR), electrophysiology study (EPS)—tests that record the heart’s activity by measuring electrical currents through the heart muscle
- Echocardiogram—ultrasound to evaluate heart structure and function
- Stress testing or cardiac catheterization—to evaluate for coronary artery disease
Leading up to your procedure:
- Talk to your doctor about your medications. You may be asked to stop taking some medications up to 1 week before the procedure.
- The night before, eat a light meal. Do not eat or drink anything after midnight.
- Ask your doctor if you should take your daily medications with a sip of water on the day of the procedure.
For the implantation of the ICD, light sedation and a local anesthesia will usually be used.
After the ICD is in place, it will need to be tested. General anesthesia will be used for this step.
Description of the Procedure
The area where the ICD is to be implanted will be washed with antiseptic. A small incision will be made below the collarbone on the left or right side.
A wire, called a lead, will be threaded through a vein in the upper chest to the heart. An x-ray monitor will be used to watch the lead move through the vein to the heart. The signals between the heart and the ICD will be carried on this lead.
A pocket will be created under the skin at the incision site. The ICD will be implanted into the pocket.
When the ICD is in place, the sedation will be increased. The ICD will be tested to make sure that it shocks the heart appropriately. Every precaution will be taken to ensure that this is a safe process. When it is determined the ICD is working properly and in the right place, the incision will be closed with stitches.
Immediately After Procedure
You will be taken to a recovery room after the procedure. Your pulse, blood pressure, and incision site will be checked regularly. Chest x-rays will ensure the ICD and leads are in the proper place.
How Long Will It Take?
About 1-3 hours
How Much Will It Hurt?
You may feel some pushing and tugging on the skin during the procedure. The anesthesia should minimize any pain. After the procedure, you may experience some pain or stiffness at the incision site. Pain medication may be prescribed.
Average Hospital Stay
At the Hospital
The day after your implant, you will have an ECG and blood tests. The ICD function may be checked again. This will require sedation.
Do the following to help ensure a smooth recovery:
You may need to avoid:
- MRI scans
- Heat therapy, which is often used in physical therapy
- High-voltage or radar machinery, such as electric arc welders, high-tension wires, radar installations, or smelting furnaces
- Contact with radio or television transmitters
- Prolonged contact with household appliances, such as microwave ovens
- Do not carry a cell phone in a pocket directly over the device. Keep your phone on the side away from the device. Also, headphones worn with MP3 players may cause interference.
- Turn off car or boat motors when working on them. They may temporarily confuse your device.
- Tell your doctor or dentist that you have a device before a surgical procedure.
- Check with your doctor about the safety of going through airport security detectors with your particular device. Do not linger in security devices.
- Be sure to follow your doctor’s instructions.
You will get an ID card that contains important information about your ICD. It is important that you show this card to any doctor, nurse, dentist, or other healthcare professional at the beginning of an office visit or hospital admission.
If your heart requires a shock from your ICD, you may be able to feel it. You may feel lightheaded before the shock. This is from the heart rhythm. The shock administered by the ICD may feel like a light thump or a strong kick in the chest. If you feel a shock, try to stay calm and sit or lie down. If someone is with you, ask him or her to stay. If you feel okay after the shock, contact your doctor’s office to let them know. This is not an emergency. Your doctor may want you to come in for a check-up, particularly if this is the first shock you have received. If you receive multiple shocks in a row or multiple shocks in a day, you should go to the emergency room.
Call Your Doctor
After you leave the hospital, contact your doctor if any of the following occurs:
- You feel a shock
- Signs of infection, including fever and chills
- Redness, swelling, increasing pain, excessive bleeding, or discharge from the incision site
- Pain that you cannot control with the medicines you have been given
- Cough or severe nausea or vomiting
These symptoms are medical emergencies. Call for medical help right away if you:
- Have chest pain or shortness of breath
- Feel lightheaded and do not feel a shock
- You are still feeling symptoms after a shock
- You feel 3 or more shocks in a row
In case of an emergency, call for emergency medical services right away.
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Last Updated: 5/11/2013