Pacemaker implantation is a procedure to put a small, battery-operated device called a pacemaker under the skin of your chest, just below your collarbone, to help your heart beat regularly.
Usually this is a minor surgical procedure performed under a local anaesthetic. Occasionally, the pacemaker may be implanted under general anaesthetic.
Why do I need a pacemaker?
To understand why you may need a pacemaker you need to know a bit about how your heart normally works. Your heart is a muscle and, like any other muscle in your body, it contracts and relaxes. The thing that we call a heartbeat is in fact your heart contracting. When you're resting, your heart normally beats (or contracts) 50 to 80 times a minute. If you exert yourself or feel anxious or stressed your heart can beat at two or three times this rate to pump blood faster around your body.
Your heart has four pumping chambers:
- two upper chambers, the "right atrium" and "left atrium", known together as the atria, and
- two lower chambers, the "right ventricle" and the "left ventricle", known as the ventricles.
The heart has its own "natural pacemaker" called the sinoatrial node (SA node), or simply the sinus node. This is a small mass of specialised cells in the top of your right atrium that generates the electrical impulses that spread throughout your heart, causing it to beat. Another group of cells called the atrioventricular node (AV node) is responsible for taking these electrical impulses down a "pathway" that runs through to the ventricles. This makes the left and right sides of the heart beat together.
If this process stops working properly you may need an artificial pacemaker. This will take over the job of your heart’s natural pacemaker all or some of the time.
The main reasons are:
- Heart block
This is when electrical impulses are not transmitted properly from your atria to your ventricles. This causes your heart to beat irregularly or more slowly than normal (bradycardia). When this happens, your brain and body don’t get enough blood. If you have "complete heart block" no electrical impulses cross to the ventricles at all. Symptoms include breathlessness, fainting or near fainting, blackouts and confusion. A pacemaker can help with heart block in some cases. If your condition is life-threatening you may need emergency surgery. In other instances a pacemaker can be fitted in a planned operation (electively).
- Arrhythmia
Arrhythmia is when you have an irregular heart rate or heart rhythm, for example your heart is beating too quickly (more than 100 beats a minute, tachycardia), too slowly (less than 60 beats a minute, bradycardia) or irregularly. Symptoms include premature beats, palpitations or skipped beats, dizziness, fatigue, light-headedness, fainting or near fainting. For bradycardia you'll need medication or a pacemaker. For tachycardia you may need medication or an implantable cardioverter-defibrillator (ICD).
- Slow natural pacemaker (sinus node disease)
This is when you have a slow natural pacemaker, which can cause different types of abnormal heart rhythm. This can happen as a result of age, heart disease or heart medications. Sinus node disease sometimes manifests as "sick sinus syndrome", in which the heart rate is sometimes very slow and sometimes very fast. Symptoms include slow or irregular pulse, palpitations, angina, shortness of breath, light-headedness, fainting, fatigue, irritability, mood swings and forgetfulness. If you have no symptoms you may not need any treatment. If you have symptoms of a slow heart rate you may need a pacemaker. If you also have a fast heart rate you may be prescribed drugs to control the rate.
- Heart failure
Heart failure is when the heart becomes less efficient at pumping blood around your body. In this case, instead of the two sides of your heart beating together they may beat at slightly different times, with the result that your heart doesn’t pump as strongly as it should. Symptoms include shortness of breath, persistent coughing or wheezing, swollen feet, ankles, legs or abdomen, tiredness and fatigue, lack of appetite, nausea and palpitations. Your treatment could include medication, a pacemaker or a pacemaker plus an implantable cardioverter-defibrillator (ICD).
