Why did I need an ICD?

The doctors may have suggested that you need an ICD because you have experienced one or both of the following.

• One or more prolonged episodes of ventricular tachycardia (an abnormally fast heart rate due to serious heart disease).
• You have had ventricular fibrillation (where the heart has rapid, unco-ordinated contractions and does not pump blood effectively) and you probably needed resuscitating with an external defibrillator.

Your fast heart rhythm could be caused by either a scar from a previous heart attack or a disorder of the heart muscle. Sometimes these serious heart-rhythm problems occur in people with otherwise normal hearts.

Having a device for these reasons is called secondary prevention.

Or the doctors may have suggested that you need an ICD for any of the following reasons.

• You have a heart condition where the pumping action of the heart is not effective and the doctors think that you are at risk of developing the fast rhythm.
• You have an inherited heart condition that puts you at high risk of experiencing fast heart rhythms.

Having a device for these reasons is called primary prevention.

Note: if you have had a cardiac arrest (that is, your heart stopped and you needed resuscitation) in the first 48 hours after having a heart attack you will not usually be considered to need an ICD. This is because cardiac arrest is not usually predicted to happen again.