Supraventricular tachycardia (SVT) is an abnormality of the heart rhythm. SVT usually occurs due to the presence of an extra nerve or pathway within the heart resulting in an electrical short circuit and a rapid, regular, heart rate.

How common is it?

SVT affects approximately 1 in 400 of the population.

What symptoms might I get?

Patients describe varying symptoms including palpitation, a fast heartbeat, shortness of breath, and giddiness. Short bursts of SVT may go unnoticed.

Will I need treatment?

Longer episodes of SVT can be controlled with simple manoeuvres such as breath holding. Your doctors will explain this to you. Some patients with SVT syndrome require treatment with drug therapy. SVT can also be improved by a procedure called electrophysiological studies and radiofrequency ablation. Small flexible electrodes are passed into the heart to identify and remove the abnormal nerve.

What extra tests are required?

You will need a heart ultrasound scan (echocardiogram) and occasionally a heart monitor.

Is it hereditary?


Does this affect my life expectancy?

Usually not, although if SVT persists for a long period of time (hours) it can cause heart failure.

What happens next?

If you have been diagnosed with SVT then you may need further treatment with your local cardiologist. Your GP should be able to arrange this.

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