Implantable cardioverter defibrillators (ICDs) can sometimes give electrical pulses or shocks that aren't needed.
A damaged wire or a very fast heart rate due to extreme physical activity may trigger unnecessary pulses. These pulses also can occur if you forget to take your medicines.
Children tend to be more physically active than adults. Thus, younger people who have ICDs are more likely to receive unnecessary pulses than older people.
Pulses sent too often or at the wrong time can damage the heart or trigger an irregular, sometimes dangerous heartbeat. They also can be painful and upsetting.
If needed, your doctor can reprogram your ICD or prescribe medicine so unnecessary pulses occur less often.
Although rare, some ICD risks are related to the surgery used to place the device. These risks include:
People who have ICDs may be at higher risk for heart failure. Heart failure is a condition in which your heart can't pump enough blood to meet your body's needs. It's not clear whether an ICD increases the risk of heart failure, or whether heart failure is just more common in people who need ICDs.
Although rare, an ICD may not work properly. This will prevent the device from correcting irregular heartbeats. If this happens, your doctor may be able to reprogram the device. If that doesn't work, you doctor might have to replace the ICD.
The longer you have an ICD, the more likely it is that you'll have some of the related risks.
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