Sick sinus syndrome: symptoms, causes, tests and pacemaker treatment

NICE explains that sick sinus syndrome is the name given to a group of heart rhythm conditions caused by a problem with the heart's natural pacemaker, the sinus node. The sinus node becomes unable to produce the electrical impulses the heart needs to beat at the normal rate. It is one of the common causes of symptomatic bradycardia, the term for a heart rate slower than normal that causes symptoms. The other common cause is atrioventricular (heart) block, and sick sinus syndrome can happen with or without it.

The NHS says heart rhythm problems (arrhythmias) are when the heart beats too quickly or too slowly, or the heartbeat is not steady, and can happen when there is a fault with the electrical system that makes the heart beat.

NICE says bradycardia may not cause any symptoms, but when symptoms do occur they include fainting, falls, dizziness, confusion, chest pain and difficulty breathing. The NHS lists symptoms of heart rhythm problems more broadly, noting that having these symptoms does not necessarily mean you have a heart rhythm problem.

• lightheadedness, dizziness or feeling like you might faint

• tiredness

• shortness of breath

• chest pain or discomfort

• heart palpitations: pounding, racing, fluttering or missing a beat

• fainting, falls or confusion (NICE)

The NHS says to see a GP if you think you may have heart rhythm problems, or if you have heart palpitations that keep happening or are getting worse. Call 999 or go to A&E if you currently have heart palpitations with chest pain, shortness of breath, feeling dizzy or lightheaded, or fainting, or feeling like you might faint. If you have had these symptoms but they have now stopped, ask for an urgent GP appointment or call 111.

The NHS says fainting is not usually serious but you should see a GP if you have fainted. Call 999 if someone has chest pain or a pounding, fluttering or irregular heartbeat with fainting, fainted while exercising or lying down, or is not breathing. You must tell the DVLA if you are fainting regularly, and must not drive if your GP has referred you to a specialist and you are waiting to be assessed.

The sources read for this guide do not give a full list of the causes of sick sinus syndrome. NICE says the problem is in the sinus node itself. The NHS lists general causes of heart rhythm problems, which can be a heart rhythm condition such as atrial fibrillation or supraventricular tachycardia, or conditions such as high blood pressure, coronary heart disease, heart valve disease or a heart attack. An abnormal heartbeat can also come from medicines, viruses, caffeine, alcohol, smoking or drugs. Your cardiologist will look for contributing factors in your case.

An ECG (electrocardiogram) records the electrical activity of the heart, including rate and rhythm, and is usually quick and painless, according to the NHS. It says there are three ways an ECG may be done: a resting ECG, a portable ECG worn over a period of time, or an exercise or medicine stress test. A portable recorder is usually worn for 24 to 48 hours, but it can be up to 7 days, to record the rhythm over a longer period.

The doctor will also ask about your symptoms and medicines. The NHS says that before a pacemaker you may need blood tests, a chest X-ray or an echocardiogram.

NICE says symptomatic bradycardia caused by sick sinus syndrome can be treated using a pacemaker. A pacemaker is a small device placed under the skin in a small surgical procedure, connected to the surface of the heart by tiny wires. It detects if the heartbeat is too slow, or if an impulse is not produced, and sends an electrical impulse to start or control the beat. Pacemakers can be single-chamber, connected to either the upper or lower chamber of the heart, or dual-chamber, connected to both.

The NHS says that, depending on the type of heart rhythm problem, many people do not need any treatment and only regular check-ups, and that possible treatments for heart rhythm problems include medicines, ablation, cardioversion and a pacemaker.

The NHS says a standard pacemaker is fitted in hospital by a cardiologist and usually takes about an hour. You have a local anaesthetic to numb the chest, and may have medicine to help you relax. A small cut is made on the left side of the chest, wires are guided through a vein to the heart and the pacemaker is placed near the collarbone under the skin. You will usually stay in hospital overnight.

After the procedure you will feel tired for a few days and the left side of your chest will be sore. The NHS says not to drive for at least the first week, and not to carry heavy objects, do vigorous exercise or lift your elbow above shoulder height for 4 to 6 weeks. You must tell the DVLA and your insurance company that you have a pacemaker.

The NHS says you will have regular follow-up appointments: about 6 weeks after the procedure at the pacemaker clinic, 3 to 6 months after with your cardiology team, and at least every 12 months after that. The battery usually lasts 6 to 7 years. You will be given a pacemaker ID card to show to healthcare professionals and airport security.

Contact your pacemaker clinic or NHS 111 if the wound becomes more swollen, tender or red, leaks blood, pus or clear liquid, you have a very high temperature or feel hot, cold or shivery, or your symptoms return or get worse. Call 999 or go to A&E for severe difficulty breathing, a tight or heavy chest, pain spreading to the arms, back, neck or jaw, pale, blue or grey lips or skin, or sudden confusion.

On the NHS, a GP can arrange an ECG and refer you to cardiology if a slow heart rhythm is suspected. NICE has appraised dual-chamber pacemakers for sick sinus syndrome as part of NHS care. Some people choose private cardiology for quicker access to monitoring and consultations. The type of pacemaker and follow-up are decided by the cardiology team in either setting.