The principle function of basic cardiac pacemakers is to treat a slow heart rate, especially when it is causing symptoms or collapses (bradycardia pacing). In this procedure which is usually performed under local anaesthetic, one or two wires known as ‘leads’ are passed into the heart.

The leads are then connected to a pacemaker box or ‘generator’ which is placed in a ‘pocket’ under the skin at the front of the chest or sometimes beneath a muscle layer.

The generator monitors the heart rate continually and if it drops below a pre-set level generates electrical impulses to ‘pace’ the heart so that it beats at a normal rate. Single chamber pacemakers have a lead in the right ventricle only and dual chamber pacemakers also have a lead in the right atrium.

National Heart Lung and Blood Institute

Biventricular pacemakers (cardiac resynchronisation therapy, CRT) can deliver bradycardia pacing but their principle function is to resynchronise any desynchrony between different parts of the muscle of the heart. This can be useful for some patients with heart failure and can reduce breathlessness. CRT requires a further lead which paces the left ventricle of the heart.

Pacemakers require indefinite specialist follow up to monitor their function, the whether any ‘shock’ therapy has been needed and determine when the battery life is running out and replacement (‘box change’ ) is needed.

Dr Dalby will discuss any proposed procedure with you including its attendant risks and benefits. When appropriate this will involve further discussion in a multidisciplinary meeting so that you may receive the best advice and reach a mutually agreeable management plan.