Atrial tachycardia is an abnormally fast heartbeat. It's the least common type of supraventricular tachycardia.

During an atrial tachycardia episode, the heart rate increases to more than 100 beats per minute before returning to a normal heart rate of around 60 to 80 beats per minute. An episode may start slowly or abruptly. Atrial tachycardia can cause light-headedness, dizziness and sometimes, fainting.

Atrial tachycardia is most commonly seen in children who have heart disorders such as congenital heart disease, particularly those who've had heart surgery. However, infection or drug or alcohol use can trigger the condition. For some people, atrial tachycardia increases during pregnancy or exercise.

Tests and procedures used to diagnose atrial tachycardia may include:

• Blood tests to check thyroid function, heart disease or other conditions that may trigger atrial tachycardia
• Electrocardiogram (ECG) to measure the electrical activity of your heart and measure the timing and duration of each heartbeat
• Holter monitor, which is a portable ECG device designed to record your heart's activity as you go about your routine
• Echocardiogram, which uses sound waves to produce images of your heart's size, structure and motion

Your doctor might also try to trigger an episode with other tests, which may include:

• Stress test, which is typically done on a treadmill or stationary bicycle while your heart activity is monitored
• Electrophysiological (EP) study and cardiac mapping, which allows your doctor to see the precise location of the irregular heartbeat (arrhythmia)

Treatment of atrial tachycardia depends on the severity of your condition and the things that trigger it. Your doctor may recommend:

• Vagal maneuvers. You may be able to temporarily slow your heart rate by holding your breath and straining, dunking your face in ice water, or coughing.
• Medications. Your doctor may suggest medication by mouth or IV to control your heart rate or restore a normal heart rhythm.
• Cardioversion. In this procedure, a shock is delivered to your heart through paddles or patches on your chest. The current affects the electrical signals in your heart and can restore a normal heart rate. Your doctor may recommend cardioversion if your arrhythmia doesn't get better with vagal maneuvers or medication.
• Catheter ablation. For this procedure, your doctor threads one or more catheters through your blood vessels to your heart. Sensors at the tips of the catheters use heat (radiofrequency) or extreme cold to damage (ablate) a small spot of heart tissue to block faulty signals that are causing your arrhythmia.
• Pacemaker. If you have frequent episodes of atrial tachycardia and other treatments haven't work, your doctor may suggest implanting a small device called a pacemaker. A pacemaker gives off electrical signals that stimulate your heart to beat at a normal rate. For people with atrial tachycardia, this procedure is typically done with ablation of the AV node.