DR MILES DALBY

Implantable cardiac defibrillators (ICD) also function as pacemakers or CRT devices but their principle function is to deliver a high energy electric shock to restore the normal heart rhythm if a patient goes into a dangerous abnormal rhythm (such as ventricular tachycardia-VT or ventricular fibrillation VT). Since ventricular fibrillation is often a fatal rhythm disturbance, ICDs can be life saving when implanted in the right patients.

ICDs are implanted in a similar way to a pacemaker with the wires (known as leads) being passed into the heart and connected to the pacemaker box ‘generator.’ The generator for an ICD is bigger than a simple pacemaker, but it is implanted similarly under the skin or beneath a layer of muscle at the front of the chest.

Since it is a bigger device than a basic pacemaker and is often tested at the end of the implant, a general anaesthetic may be recommended.

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