Major complications after the device is implanted include failure to output, and failure to respond correctly.

What does this mean?

"Failure to output" happens when the device does not respond to the heart as needed. Either the device is not listening to the signals coming from the heart, or it misreads them.

This may be caused by battery failure, a broken wire, a poor connection or over-sensing. Over-sensing occurs when the device picks up too many signals from your heart and mistakenly thinks your heart is beating properly when it is not.

These problems may require x-rays, placement of a temporary pacemaker, or lead wire replacements. Sometimes, these include a stay in the hospital and insertion of a new device, just like the original procedure. Drugs for abnormal heartbeats may also be given to treat these problems. Or, external defibrillation may be required. This is done at a hospital or in an ambulance if your city is equipped with this emergency equipment.

"Failure to respond" happens when the device responds to your heart, but your heart does not respond to the device.

This may be caused by broken, disconnected or damaged wires, a blood clot at the tip of the wire, a tear in the heart, certain drugs, or abnormalities in your blood chemistry.

These complications may require the same methods we just mentioned and also the correction of blood chemistry and blood clots.