Why might I need a device?

Several types of arrhythmia can be treated with a pacemaker or defibrillator. With some of these, there may be other treatments, depending on the cause of the problem.

Heart block

Heart block causes your heart to beat very slowly and has many causes. It sometimes occurs after a heart attack or surgery. If so, it may go away during recovery, but it may persist if there is scarring of the heart's conductive tissue.

Heart block is divided into three stages, depending on the severity:

  • First-degree heart block may be symptom-free and doesn't need treatment
  • Second-degree heart block often requires a pacemaker
  • With third-degree heart block, you’ll almost certainly need a pacemaker. In an emergency, a temporary pacemaker may be used until you can have a permanent pacemaker implanted

Bradycardia (slow heartbeat)

Bradycardia is an arrhythmia that may be experienced as ‘syncope’ (sudden fainting) or moments of light-headedness.

It can be caused by an underactive thyroid or obstructive sleep apnoea. Certain medications, including some used to treat other heart conditions, may also cause bradycardia.

Bradycardia can also be caused by damage to your heart’s electrical system, resulting in weakness, fatigue or difficulty when exercising.

Ventricular tachycardia (fast heartbeat)

Ventricular tachycardia is a different rhythm from normal, resulting in a very rapid heart rate and very low blood pressure. It has a number of causes, almost all resulting from damaged heart muscle.

Ventricular tachycardia can put you at risk of a more dangerous arrhythmia, called ventricular fibrillation.

Ventricular fibrillation

This is a life-threatening condition in which electrical impulses stimulate your heart over 250 times per minute. At this rate, the chambers of your heart can’t contract in a coordinated way and blood isn’t effectively pumped through your body. After three to four minutes, brain damage and death can occur.

When they diagnose ventricular fibrillation, paramedics and hospital personnel place paddles on your chest and deliver a high voltage shock that travels to your heart to stimulate it. If this is successful, your normal heart rhythm is restored. Your doctor may then recommend an implantable defibrillator.

Heart failure

Heart failure is a condition in which your heart can’t pump enough blood to meet your body’s needs. The main cause is damage following a heart attack or cardiomyopathy, a disease which affects the heart muscle.

A pacemaker, or an implantable defibrillator are options for helping the heart pump and preventing sudden cardiac arrest. 

Treatments to consider before opting for surgery

Treatment of underlying conditions or medication may be the first step.


Information is provided by HCF in good faith for the convenience of members. It is not an endorsement or recommendation of any form of treatment nor is it a substitute for medical advice, and you should rely on the advice of your treating doctors in relation to all matters concerning your health. Every effort has been taken to ensure the accuracy of the information, however HCF takes no responsibility for any injury, loss, damage or other consequences of the use of this information.