Tachycardia is a common heart rhythm disorder (arrhythmia) in which the heart beats faster than it should while at rest. You heart rate will increase naturally during exercise or as a physiological response to stress, trauma or illness. However, in tachycardia the heart beats faster than normal whilst in a resting state.

Tachycardia happens when the electrical system that controls your heart rhythm is not working properly. It causes your heart rate to suddenly beat much faster, it can then slow down abruptly. Normal heart rates are between 60-100 beats per minute.

There may be no symptoms of tachycardia other than a suddenly faster heartbeat, or you may experience chest pain, feel weak, breathless or lightheaded. You may feel tired and nauseous.

There are many possible causes of tachycardia. It could be as a result of damages heart tissue from heart disease, abnormal electrical pathways present at birth (congenital heart disease), anemia, exercise, sudden stress, high or low blood pressure, fever, smoking, excess alcohol or caffeine. It could also be a side effect of some medications, or an overactive thyroid. In some cases, the cause may not be known.

Possible complications from tachycardia can vary in severity but can include blood clots that can cause a stroke or heart attack. Heart failure, from the hearts inability to pump enough blood around the body. Dizzy spells or frequent fainting or in extreme case sudden death.

Treatment for tachycardia are designed to treat the cause if it is known, as well as slow the heart rate, prevent further episodes and minimize complications.

They may include:

Medications – anti-arrythmic medications are administered via injection.

Cardioversion – a small electric shock to help get the heart back to its natural rhythm

Catheter ablation – a procedure to scar or destroy tissue that’s allowing incorrect signals to cause abnormal heart rhythms.

Pacemaker – a small device that is implanted under the skin to help control the heart rate.

Implantable cardioverter – this device continuously monitors and detects any increases in your heart rate, delivering electrical shocks if needed to restore normal heart rhythm.

Open heart surgery may be needed in some cases to destroy an extra electrical pathway causing tachycardia.