An implantable cardioverter defibrillator (ICD) is a small electronic device connected to the heart. It is used to continuously monitor and help regulate potentially fast and life-threatening electrical problems with the heart.
The ICD, about the size of a stopwatch, is implanted under the skin just below the collarbone. It consists of a pulse generator and wires, called leads. The pulse generator contains the battery and a tiny computer. One or more lead wires connect the pulse generator to specific locations in the heart.
The ICD responds to irregular life-threatening heart rhythms from the lower chambers of the heart with pacing that corrects a fast rhythm and promotes a normal heartbeat, or a shock (defibrillation) that resets the heart rhythm to prevent sudden cardiac arrest. An ICD also records and stores information about your heart rhythm and therapies delivered by the ICD for your doctor to review.
Most people are unaware when the ICD is pacing the heart. But, a defibrillation shock is described by many as feeling like a "kick in the chest."
The ICD can also be programmed to work as a basic pacemaker as needed. Sometimes after a shock is delivered, the heart may beat too slowly. The ICD has a "back-up" pacemaker, which can stimulate the heart to beat faster until the normal heart rhythm returns. The ICD can act as a pacemaker any time the heart rate drops below a preset rate.
You may need an ICD if you have survived sudden cardiac arrest due to ventricular fibrillation, or have fainted due to ventricular arrhythmia, or if you have certain inherited heart conditions.
An ICD is generally needed for those at high risk of cardiac arrest due to a ventricular arrhythmia. This includes people with heart failure who have problems with the contraction of the heart, such as abnormal left ventricular ejection fraction.
There may be other reasons for your doctor to recommend an ICD.
Possible risks of ICD insertion include:
If you are pregnant or think that you could be, or are currently breastfeeding, tell your healthcare provider.
If you are allergic to or sensitive to any medicines or latex, tell your healthcare provider.
Lying still on the procedure table for the length of the procedure may cause some discomfort or pain.
There may be other risks depending on your specific medical condition. Be sure to discuss any concerns with your healthcare provider before the procedure.
Having an ICD implanted may be done on an outpatient basis or as part of your stay in a hospital. Procedures may vary depending on your condition and your doctor’s practices.
Generally, an ICD insertion follows this process:
After the procedure, you may be taken to the recovery room for observation or returned to your hospital room. A nurse will monitor your vital signs.
Tell your nurse right away if you feel any chest pain or tightness, or any other pain at the incision site.
After the period of bed rest has been completed, you may get out of bed with help. The nurse will help you the first time you get up, and will check your blood pressure while you are lying in bed, sitting, and standing. Move slowly when getting up from the bed to avoid any dizziness from the period of bed rest. You will be able to eat or drink once you are completely awake.Your arm may be in a sling for a day or so. How long you will need to wear a sling will depend on your provider. Some people are asked to wear it at night while they sleep after the first couple of days but can take it off during the day.
The insertion site may be sore or painful, and pain medicine may be given if needed.After the procedure, a chest X-ray is often done to check the lung and make sure the systems are stable.
Your doctor will visit with you in your room while you are recovering. The doctor will give you specific instructions and answer any questions you may have.
Once your blood pressure, pulse, and breathing are stable and you are alert, you will be taken to your hospital room.
If the procedure is done on an outpatient basis, you may be able to leave after you have completed the recovery process. However, it is common to spend at least 1 night in the hospital after ICD implantation for observation.
Arrange to have someone drive you home from the hospital after your release.
You should be able to return to your daily routine within a few days. Your doctor will tell you if you need to take more time in returning to your normal activities. Avoid lifting or pulling on anything for a few weeks. You may be told to limit movement of the arm on the side that the ICD was placed, based on your doctor's preferences.
You will most likely be able to resume your usual diet, unless your doctor tells you differently.
Keep the insertion site clean and dry. You will be given instructions about bathing and showering. Your doctor will give you specific instructions about driving. You will not be able to drive until your doctor says it's OK. These limitations will be explained to you, if they are applicable to your situation.
You will be given specific instructions about what to do the first time your ICD delivers a shock. For example, you may be told to dial 911 or go to the nearest emergency room in the event of a shock from the ICD. Calming yourself with slow deep breaths can be helpful if you are anxious after a shock.
Ask your doctor when you will be able to return to work. The nature of your job, your overall health, and your progress will determine how soon you may return to work.
After implantation, your ICD will require regular evaluation (called an interrogation) to evaluate its function and battery status, and to check for any significant events stored by the device. Your doctor will tell you when and how this is done.A home monitor may be provided to you that can communicate with your ICD wirelessly. Information about ICD function can then be related to your doctor over the internet.
Tell your doctor right away if you have any of the following:
Your doctor may give you other instructions after the procedure, depending on your particular situation.
Take the following precautions when you have an ICD implanted. Discuss the following in detail with your doctor, or call the company that made your device:
Before you agree to the test or the procedure make sure you know: