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What are the Risks of Defibrillator Insertion?

Defibrillator implantation is a very common and low risk procedure and should a complication arise, it will be dealt with at once.

Although most people undergoing defibrillator implantation do not experience any complications, you should be aware of the following risks:

  • Haematoma (large bruise) - this may occur at the pacemaker insertion site. This may be uncomfortable and can take several weeks to settle.

  • Pneumothorax –During the procedure it is necessary to insert the pacemaker leads into your heart via a small vein under the collar-bone. This vein runs very close to the lung and there is a small chance that a small hole could be inadvertently made in the lung (Pneumothorax). Should this occur, it would usually heal by itself. However, occasionally a small tube may need to be inserted to drain out the air. This can be uncomfortable and means spending several extra days in hospital.

  • Lead Dislodgment. – Although a great deal of care is taken in placing the pacemaker leads inside your heart, occasionally one of them moves and will need to be repositioned. This usually occurs in the first 24 hours after the procedure and is detected by testing the pacemaker.

  • Infection – There is a very small chance that the pacemaker will develop an infection. Should this occur, it is usually necessary to remove the pacemaker in order to clear the infection.

  • Cardiac perforation – Very rarely, one of the leads can make a small hole in the heart causing blood to accumulate around the heart. If this occurs the problem will be dealt with immediately. This is a very rare occurrence.

Testing the device. – During the procedure it is necessary to test the device to ensure it works properly. This involves inducing the life-threatening rhythm disturbance termed ventricular fibrillation. The device will promptly revert this back to normal but if it does not, the rhythm will be immediately corrected by a high energy shock delivered to the outside of the chest.

Although there is a theoretical risk that the rhythm could not be reverted this risk is extremely small and has never occurred at the Royal Melbourne Hospital. Occasionally, due to the type of heart condition you have, your doctor will decide not to test the device at the time of the implant. This will be discussed with you.

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Melbourne Heart Rhythm is the arrhythmia service at the Department of Cardiology at the Royal Melbourne Hospital. We are comprised of a team of highly trained and dedicated health care professionals specializing in heart rhythm management. We have a strong focus on patient education and patient centered care. Our arrhythmia specialists have an international reputation of excellence in arrhythmia research and clinical arrhythmia management.