What do pacemakers do

A.� Pacemakers generally speed up heartbeats that would otherwise be dangerously slow.

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Q.� How do pacemakers work

A.� The pacemaker generates small electrical pulses that cause the heart to contract at the correct intervals, keeping it beating at the right speed.

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Q.� Are pacemakers only used for heartbeats that are too slow

Q.� No, they can also be used in cases where the heartbeat isn't strong enough or to slow down a heartbeat that is too fast.

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Q.� Why isn't medication used instead

A.� There are many forms of medication that slow down a heart that is beating too fast but relatively few for speeding up a heart. Of these, many have bad side effects and are often rejected by the body.

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Q.� Is having a slow heart beat fatal

A.� It can be, it can also cause the patient to faint.

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Q.� What causes a slow heart beat

A.� Normally, the affected heart is missing a critical cell that should maintain a safe beat rate or there's a block in the heart's electrical pathways, obstructing the normal flow of electrical currents to its muscles. Such blocks can be the result of scar tissue left after heart attacks.

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Q.� The heart needs to beat at different rates sometimes. What happens then

A.� Modern pacemakers are designed to respond to a person's activity: they go faster when the patient is active and slower when the patient is resting.

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Q.� What is a pacemaker composed of

A.� It contains a pulse generator, along with the battery and circuits, housed in a small plastic case, not much bigger than a�50p piece. Connected to it is a lead, which is attached to the heart muscles and along which the electrical pulse is sent.

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Q.� Isn't it dangerous sending electrical pulses through the heart

A.� No, in fact pacemakers are only replicating the electrical currents that the heart generates naturally to make it beat. Spread over the heart is a group of cells that generate their own electrical pulses, causing it to contract and create��a heartbeat - normally 72 times a minute.

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by Lisa Cardy