The sinus node is the heart’s pacemaker and if it isn’t working properly you will experience arrhythmias – abnormal or irregular heart beat.
Sick sinus syndrome is the name given to this group of arrhythmias.
The sinus node is situated in the upper right-hand chamber of the heart and consists of specialized cells that produce regular electrical impulses which trigger the rhythmical beating of the heart.
In sick sinus syndrome, the sinus node doesn’t produce regular impulses, which causes a slow heart rate, called bradycardia, a fast heart rate, called tachycardia, or an alternating irregular beat.
Sick sinus syndrome mainly affects people who are aged over sixty, and it is largely caused by normal wear and tear. Although it isn’t a very common condition, it can occur in infants, or it may be related to other diseases like muscular dystrophy.
If the heart beat is very irregular, a pacemaker may need to be fitted to do the work of the sinus node. Symptoms can be erratic or there can be no symptoms.
Those that do occur are similar to other heart problems – fatigue, dizziness, shortness of breath, chest pain, palpitations and confusion. Most of these symptoms are because of the reduced flow of blood to the brain.
There are various tests that can be performed to confirm a diagnosis of sick sinus syndrome. An electrocardiogram is usually the first test done, but if your irregular heart beat isn’t present all the time, this ECG may not pick it up.
There are two different types of portable ECG that you wear at home – the Holter monitor records your heart’s activity for a full 24 hours; and the event recorder ECG only records when you press a button, which you do when you feel the symptoms coming on. These allow the specialist cardiologist to examine your heart beat and detect the irregularity.
Treatments for sick sinus syndrome are aimed at reducing the symptoms, which can be quite unpleasant to the patient. If you are not troubled by your symptoms, there is usually no treatment, but you will be regularly monitored.
If you have been on medications, these could be monitored to see if they have been affecting your heart rhythm, and adjusted if necessary.
The preferred treatment for severe symptoms of bradycardia and tachycardia is an electronic pacemaker that is implanted under the skin, near the collarbone. There are different types of electronic pacemaker, and the one best suited to your condition will be fitted.