Pacemaker implantation - Risks of pacemaker implantation

As with any medical or surgical procedure, pacemaker implantation has risks as well as benefits. Some of the main risks are described below.

Blood clots

In about one in every 50 cases, a blood clot develops in one of the veins in the arm on the side of the body where the pacemaker was fitted.

This may cause some swelling in the affected arm, but it usually settles in a few days and is rarely a serious problem.

In some cases, you may be given anticoagulant medication, which stops the clot getting bigger.

Pacemaker infection

It is estimated that around one in 100 people with a pacemaker will develop a pacemaker infection. This usually happens within the first 12 months of having a pacemaker fitted.

Symptoms of a pacemaker infection include:

• a high temperature of 38°C (100.4°F) or above
• pain, swelling and redness at the site of the pacemaker

If you're worried that you have developed an infection, call your GP or cardiologist as soon as possible for advice. If this is not possible, call NHS 111 or your local out-of-hours service.

A pacemaker infection is usually treated using a combination of antibiotics and surgery to remove and then replace the pacemaker.

If an infection is not treated, it could spread into your lungs (pneumonia), the lining of your heart (endocarditis) or your blood (sepsis).

Air leak

As the vein through which the pacemaker wires are sometimes inserted lies very close to one of the lungs, there is a risk of the lung becoming punctured accidentally during pacemaker implantation. This means that air can leak from the affected lung into the chest area.

This problem is known as pneumothorax and it's estimated to occur in about one in every 100 pacemaker implantation procedures.

In most cases, the leak is very small and gets better on its own without treatment. If a lot of air leaks into the chest, this may need to be sucked out using a needle and by placing a special drain into the chest area.

If a drain is required, you may need to stay in hospital for an extra day or two.

Problems with the pacemaker

As with any electronic device, there is a small chance that your pacemaker could stop working properly. This is known as a pacemaker malfunction. 

A pacemaker can go wrong if:

• the lead gets pulled out of position
• the battery of the pulse generator fails
• the circuits that control the pacemaker become damaged by exposure to strong magnetic fields
• the pacemaker has not been properly programmed

It's estimated that the pacemaker leads become dislodged in more than one in 100 cases, but a problem with the pacemaker itself is estimated to occur in only one in every 400-500 cases.

Signs that your pacemaker may have failed include:

• your heart begins beating more slowly or quickly
• dizziness
• hiccups
• fainting or nearly fainting

As with a pacemaker infection, seek immediate medical advice if you're concerned that your pacemaker has failed.

In some cases, it may be possible to correct a pacemaker remotely using wireless signals or magnets. Otherwise, the pacemaker will need to be removed and replaced.

Twiddler’s syndrome

An often overlooked cause of pacemaker malfunction is known as twiddler’s syndrome.

This is when the pacemaker generator is pulled out of its normal position because a person is – often without realising – moving the generator under the skin back and forth or round and round (twiddling with it).

One treatment option is to stitch the generator more firmly to the surrounding tissue so it cannot be moved.