Long Q-T Syndrome (LQTS)

What is the long Q-T syndrome (LQTS)?

Long Q-T syndrome (LQTS) is a form of heart disease. It gets its name from the unusual pattern of the electrocardiogram (ECG) of people with the disease. It sometimes results in life-threatening heart rhythm problems.

How does it occur?

LQTS runs in families and can be caused by a number of different gene defects. These defects affect the ability of the heart's muscle cells to use sodium and potassium properly. As a result, abnormal heart rhythms occur off and on. Some of these rhythms may be very fast and cause symptoms. LQTS is often present at birth but can appear at any age. It most often occurs in children and young adults.

What are the symptoms?

The most common symptom is fainting at a time of stress. The stress may be physical or emotional. It could be just playful tickling. Fainting spells are usually brief, but injuries can occur from falling at the time of fainting. Sometimes people have both fainting spells and seizures. The most serious symptom is sudden loss of consciousness followed by death.

Some people with LQTS have few or no symptoms. Even so, they do have an increased risk of life-threatening heart rhythms.

How is it diagnosed?

Your healthcare provider will ask about your medical history, including your symptoms. Your provider will also ask if any of your family members have had LQTS, unexplained fainting spells, or sudden death. If you faint during emotional or physical stress, LQTS is a likely possibility.

You will have an ECG to measure the electrical activity of your heart. If a certain pattern shows on the ECG, you may be diagnosed with LQTS. Because it runs in families, other family members should also be tested.

How is it treated?

For treatment your healthcare provider may refer you to a cardiologist who specializes in heart rhythms (an electrophysiologist).

Your provider may prescribe a type of medicine called a beta blocker. The heart rhythms of people with LQTS are very sensitive to adrenalinelike chemicals produced by their bodies. Blocking these chemicals helps relieve symptoms. Beta blockers can reduce heart rhythm problems when you have LQTS.

Most people also benefit from treatment with a pacemaker to speed up the heart rate slightly.

You may need an implantable cardiac defibrillator (ICD). An ICD is a device that monitors the heart and shocks it back into a normal rhythm if a life-threatening heart rhythm is detected.

How long will the effects last?

With treatment, people with LQTS can lead fairly normal lives. Most can be physically active and handle emotional stress without fear of symptoms. You may need to avoid some activities, such as being a flying planes or scuba diving. Ask your healthcare provider about this.

How can I help take care of myself?

Your healthcare provider will develop guidelines for your treatment. They will include recommendations about physical activity.

Call your healthcare provider right away if:

• You have spells of lightheadedness or fainting.
• You feel your heart racing for short spells.