Cardioverter Defibrillator Implantation

An implantable cardioverter defibrillator (ICD) is a small, lightweight, battery-powered device that is placed (implanted) under the skin in the chest or abdomen. Your caregiver may prescribe an ICD if:

  • You have had an irregular heart rhythm (arrhythmia) that originated in the lower chambers of the heart (ventricles).

  • Your heart has been damaged by a disease (such as coronary artery disease) or heart condition (such as a heart attack).

An ICD consists of a battery that lasts several years, a small computer called a pulse generator, and wires called leads that go into the heart. It is used to detect and correct two dangerous arrhythmias: a rapid heart rhythm (tachycardia) and an arrhythmia in which the ventricles contract in an uncoordinated way (fibrillation). When an ICD detects tachycardia, it sends an electrical signal to the heart that restores the heartbeat to normal (cardioversion). This signal is usually painless. If cardioversion does not work or if the ICD detects fibrillation, it delivers a small electrical shock to the heart (defibrillation) to restart the heart. The shock may feel like a strong jolt in the chest. ICDs may be programmed to correct other problems. Sometimes, ICDs are programmed to act as another type of implantable device called a pacemaker. Pacemakers are used to treat a slow heartbeat (bradycardia).


  • Any allergies you have.

  • All medicines you are taking, including vitamins, herbs, eyedrops, and over-the-counter medicines and creams.

  • Previous problems you or members of your family have had with the use of anesthetics.

  • Any blood disorders you have had.

  • Other health problems you have.


Generally, the procedure to implant an ICD is safe. However, as with any surgical procedure, complications can occur. Possible complications associated with implanting an ICD include:

  • Swelling, bleeding, or bruising at the site where the ICD was implanted.

  • Infection at the site where the ICD was implanted.

  • A reaction to medicine used during the procedure.

  • Nerve, heart, or blood vessel damage.

  • Blood clots.


  • You may need to have blood tests, heart tests, or a chest X-ray done before the day of the procedure.

  • Ask your caregiver about changing or stopping your regular medicines.

  • Make plans to have someone drive you home. You may need to stay in the hospital overnight after the procedure.

  • Stop smoking at least 24 hours before the procedure.

  • Take a bath or shower the night before the procedure. You may need to scrub your chest or abdomen with a special type of soap.

  • Do not eat or drink before your procedure for as long as directed by your caregiver. Ask if it is okay to take any needed medicine with a small sip of water.


The procedure to implant an ICD in your chest or abdomen is usually done at a hospital in a room that has a large X-ray machine called a fluoroscope. The machine will be above you during the procedure. It will help your caregiver see your heart during the procedure. Implanting an ICD usually takes 1–3 hours. Before the procedure:

  • Small monitors will be put on your body. They will be used to check your heart, blood pressure, and oxygen level.

  • A needle will be put into a vein in your hand or arm. This is called an intravenous (IV) access tube. Fluids and medicine will flow directly into your body through the IV tube.

  • Your chest or abdomen will be cleaned with a germ-killing (antiseptic) solution. The area may be shaved.

  • You may be given medicine to help you relax (sedative).

  • You will be given a medicine called a local anesthetic. This medicine will make the surgical site numb while the ICD is implanted. You will be sleepy but awake during the procedure.

After you are numb the procedure will begin. The caregiver will:

  • Make a small cut (incision). This will make a pocket deep under your skin that will hold the pulse generator.

  • Guide the leads through a large blood vessel into your heart and attach them to the heart muscles. Depending on the ICD, the leads may go into one ventricle or they may go to both ventricles and into an upper chamber of the heart (atrium).

  • Test the ICD.

  • Close the incision with stitches, glue, or staples.


  • You may feel pain. Some pain is normal. It may last a few days.

  • You may stay in a recovery area until the local anesthetic has worn off. Your blood pressure and pulse will be checked often. You will be taken to a room where your heart will be monitored.

  • A chest X-ray will be taken. This is done to check that the cardioverter defibrillator is in the right place.

  • You may stay in the hospital overnight.

  • A slight bump may be seen over the skin where the ICD was placed. Sometimes, it is possible to feel the ICD under the skin. This is normal.

  • In the months and years afterward, your caregiver will check the device, the leads, and the battery every few months. Eventually, when the battery is low, the ICD will be replaced.