If you are at risk of ventricular arrhythmia, your doctor may recommend you receive an implantable cardioverter defibrillator (ICD) to detect and correct dangerous heart rhythms in the heart’s lower chambers, or ventricles.
The ICD is a small, battery-powered device that is surgically placed in the chest wall below the collarbone or under the armpit. It uses an electrical wire to constantly monitor the heart rate and rhythm for irregularities. There are two types of ICDs: the traditional device with wires connected directly to the heart, and the subcutaneous ICD, which uses an electrode that is placed under the skin and near——but not connected to—the heart.
When a life-threatening arrhythmia is detected, the device delivers an electrical shock or shocks through flexible, insulated wires, called leads, which extend from the device to or near the heart. The shock resets the heart’s electrical pacing and restores a normal heart rate and rhythm.
When the heart begins to beat too fast, the ICD delivers small electrical pacing impulses that coax the heart back into a normal rhythm. Most people do not feel this pacing. Larger shocks, however, tend to feel like an uncomfortable “thump” in the chest.
The surgery to implant a cardioverter defibrillator typically takes about an hour. Until your follow-up appointment 2 weeks after surgery, your doctor may restrict your activity, including telling you not to lift anything heavier than 10 pounds.
If you are at risk of fainting from a fast or irregular heart rhythm, driving may be restricted for longer periods of time or permanently. This is a result of the condition, not the device.
An ICD contains a pulse generator, or computer, that stores information about when and how many electrical shocks are delivered from the device to the heart. It also measures the status of the device’s battery, which typically lasts 5 to 10 years, at which time the device is replaced.
Cardiac device management experts monitor people with ICDs via information transmitted to our office either by phone or wireless connections. Reports are reviewed each business day morning. Our specialists contact you when they receive a report that the ICD was triggered to ensure you receive follow-up care.
Remote monitoring is not an emergency system. If you feel a shock, please call your doctor or visit the nearest emergency department. If you receive two or more shocks within a few minutes, please call 911 for emergency assistance. Do not drive yourself to the emergency department.
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