SUPRAVENTRICULAR TACHYCARDIA

What is it?

The way the heart works is by the heart muscles squeezing blood through the inside of the heart and out into the main blood vessels. Electrical circuits inside the heart make the muscles contract in the right order and at the right speed. A supraventricular tachycardia, or SVT, is a sort of electrical short-circuit which allows the heart muscle to pump very fast. Sometimes this means the muscle does not have time to relax between squeezes so that it can't pump as well as usual. Although SVTs are uncomfortable and unpleasant, they hardly ever do any serious damage. If you are told that you have SVTs you should not be too anxious about it. It does not mean that your heart is diseased or damaged.

Who gets them?

Anyone can get SVTs. You can get them for the first time at any time from early in childhood to adulthood.

What are the symptoms?

The first thing you will notice is a sudden feeling that the heart is beating very fast - palpitations. You might also feel faint or breathless, and sometimes you might feel some chest pain. You may feel you need to pass water a lot when you have an SVT. If an SVT goes on for too long you may find yourself getting short of breath.

When should I go to my GP?

If you have palpitations that go on for a long time and make you feel faint, you should see your GP as soon as possible. If you feel very breathless and unwell you should go straight to hospital. Since SVTs usually stop on their own sooner or later, you can often afford to wait for a routine appointment - as long as you feel fine otherwise.

What tests will my Doctor want to do?

Your GP will give you a check-up and will probably want to send you for a tracing of your heartbeat, called an ECG. You may need to wear a heart monitor, which you can carry around with you, for one or two days. This is to give your GP a chance to get a tracing when you're actually having an attack.

What is the short-term treatment?

You can often stop an SVT simply by massaging your neck on one side - your doctor can show you how. If you have a bad SVT you may need an injection of a certain medicine.

Will I need long-term treatment?

This depends on how bad your symptoms are. If you get SVTs often, you may need to take regular tablets. If you smoke, or drink too much alcohol, it may help to cut down or stop. It can also help if you don't take too much caffeine, so cut down on tea or coffee and have no more than a few cups a day. If you suffer a lot of stress and tension, try some relaxation exercises.

Will I have to go to hospital?

You may need to go to the hospital for your heart tracing and if you have a lot of SVTs you might need an appointment with a heart specialist to sort out the right treatment for you. Very occasionally, if your symptoms are very hard to sort out, you may need an operation.

A DOCTOR information leaflet for patients