An implantable cardioverter-defibrillator (often called an ICD) is a device that briefly passes an electric current through the heart. It is "implanted," or put in your body surgically. It includes a pulse generator and one or more leads. The pulse generator constantly monitors your heartbeat. It is like a small computer that runs on a battery. The lead (pronounced "leed") is a wire from the pulse generator to the inside of your heart. The lead takes signals from your heart to the ICD and then takes an electric current from the pulse generator to your heart.
Why Would I Need an ICD?
Normally, your heart has a natural pacemaker that helps your heart beat steadily. An electrical current starts in one of the upper chambers (called atria) of the heart and goes through the heart to the bottom chambers (called ventricles). You may need an ICD if you have had, or are at risk of having certain heart rhythm problems.
How Does an ICD Work?
The ICD watches your heart rhythm. If it sees your heartbeat is irregular, it delivers the treatment programmed by your doctor. The ICD can perform:
Pacing: If you have ventricular tachycardia that isn't too fast, the ICD can deliver several pacing signals in a row. When the signals stop, the heart may go back to a normal rhythm.
Cardioversion: If pacing doesn't work, cardioversion is used. A mild shock is sent to the heart to stop the fast heartbeat.
Defibrillation: If ventricular fibrillation is detected, a stronger shock is sent. This stronger shock can stop the fast rhythm and help the heartbeat go back to normal.
Pacemaking: The ICD can also see when your heart beats too slowly. It can act like a pacemaker and bring your heart rate back up to normal.
How is an ICD Implanted?
The pulse generator may be implanted under you collarbone, or in your abdomen. The doctor will make a pocket under your skin or in a muscle to put the generator in. One end of the lead wire is put into a vein that goes to your heart. The wire is moved through the vein until it reaches the heart. The other end of the wire is attached to the pulse generator. Once implantation is complete, your doctor will program the ICD to treat your specific heart rhythm problem.
How Will I Look and Feel with My ICD?
To most people you will look exactly the same. Your partner or family will be aware of the implant. The ICD's pulse generator is smaller than a deck of cards, but you may see a small bulge under your skin. You may have one or two incisions, and will have a scar at each incision. The scars will be less visible as time goes by.
If you have an abdominally implanted ICD you may feel a slight tingling if you lean on a counter or hard surface. It does not harm the ICD. The tingling will not hurt you. You may also feel the weight of the pulse generator in some activities such as bowling, golfing or hunting. This will become less noticeable as time goes by.
Your regular clothing should be comfortable for you to wear. Men can wear suspenders or a belt depending on the implant site. Women can wear a loose belt, or skirts and pants with a loose waistband. For pectoral (upper chest) implants, comfortable bras should be worn. How long it takes to adjust to your ICD varies with each person. As you adjust to your ICD, you will begin to feel more comfortable.
You have experienced many changed because of your tachyarrhythmia and ICD implant. It is normal to have many emotions including relief, comfort, anxiety, fear and anger to come and go over the course of many months.
Talk about your concerns and feelings, it will make it easier for you to adjust. Talk to someone you trust, your doctor, another ICD patient, or a friend. Join a support group like the Zapper Club. The goal is for you to lead a normal life as soon as possible!
How will the ICD Affect My Lifestyle?
Your doctor will want you to limit your activities for the first few weeks so that you will heal well. Then you can slowly go back to your normal lifestyle. Depending on your condition and local laws, your doctor will tell you if you will be able to drive your car. You should be back to normal after a month.
You will need to stay away from machines that could interfere with your ICD. You shouldn't work near strong magnetic or electric fields. The ICD is built to be protected from most home shop tools and electric appliances, including microwave ovens. However, you need to be certain that all electric items are properly grounded and in good repair. Your doctor will help you understand what to avoid.