A pacemaker is a small, battery-operated device which sends impulses across the heart to make it beat at an optimum rate. It is inserted under the skin, usually on the left side of the chest, under local anaesthetic, often with mild sedation. 1 or 2 leads from the pacemaker are then guided by xray through a vein under the collar bone to the heart. Moving the leads inside the heart is entirely painless.


Pacemakers are normally used when the natural heart rate is too slow (or occasionally when it is too fast), and are extremely reliable but require long-term monitoring. A 3-4cm scar may be left following the procedure, and there may be a small bump where the pacemaker lies.

Other risks of the procedure include:

  • A collapsed lung (1-2%) which normally does not require further treatment; occasionally, it is necessary to insert a chest drain to re-inflate the lung;

  • The leads becoming dislodged (2-3%). An xray and ECG are carried out following the procedure and the lead repositioned, if necessary, before discharge home;

  • Bruising over the pacemaker. This is usually of no consequence, although if a collection of blood gathers at the site of the pacemaker that becomes too large, it may be necessary to drain it; and

  • Infection (less than 1%). All patients are treated with antibiotics to minimise this risk.