Your heart may beat too fast at times or beat both too slow and too fast at different times. If these conditions cannot be controlled using medication then you may need a pacemaker. The job of a pacemaker is to artificially take over the role of the heart's natural pacemaker (the sino atrial node), either all of the time, i.e. at a 'fixed rate' or some of the time, i.e. 'on demand'. Most pacemakers can be programmed to send electrical impulses to the heart at a rate that suits your particular needs. Pacemakers are inserted under local anesthetic. They need checking regularly by specialist technicians at a pacemaker clinic. Pacemakers are powered by a battery and usually last between six and ten years before they need to be replaced.
Pacemakers are most often needed for those whose heart rate has become too slow. There are many reasons why this might happen:
• you may have heart block (when the electrical impulses are not being transmitted properly from the atrium to the ventricles - see below). The arrhythmia section has further information about how the heart beats normally
• you have an irregular heart rate or heart rhythm - for example if your heart beats too rapidly (tachycardia syndrome), or too slowly (bradycardia syndrome), or irregularly
• you have a slow natural pacemaker (sinus node disease - see below), or
• you have heart failure.
Heart block is usually caused by heart disease or by the heart aging. It may also develop after a heart operation - as either a short-term or long-term condition. With certain types of heart block, the doctor will recommend a cardiac pacemaker to help regulate the heartbeat. Some people develop slow heart rhythms which can be life-threatening, and they may need to have a pacemaker fitted as an emergency, but others can arrange to have their pacemaker fitted at a later date.
Sinus Node Disease
If you have sinus node disease, it means that your sinus node is not working properly. This can result in different types of abnormal heart rhythms. Sinus node disease sometimes develops into 'sick sinus syndrome' where you may have a heart rate that is sometimes very slow and sometimes very fast. If you don't have any symptoms, you may not need any treatment. However, if you have symptoms that are related to a slow heart rate, you may need a permanent implanted pacemaker. If you also have a fast heart rate, you may be given drugs to control the rate.