What is long qt syndrome?

Long QT Syndrome

What are the symptoms of long QT syndrome (LQTS)?

Some people don't have symptoms. But in those who do, symptoms include fainting, seizures, and feeling dizzy or lightheaded. Heart palpitations also can occur. LQTS can also cause sudden cardiac arrest. This means that the heart suddenly stops beating. In some people, symptoms may be triggered by exercise, stress, or being startled.

How is long QT syndrome (LQTS) treated?

Treatment depends on symptoms and whether the condition is genetic or caused by something else. Treatments include medicines to change the heart rhythm and an implanted device to prevent life-threatening heart rhythms. Some people have surgery. Most people need to avoid strenuous exercise. People also need to avoid medicines that can cause the condition.

How is long QT syndrome (LQTS) in children diagnosed?

The doctor will do a physical exam. The doctor will also ask questions about your child's symptoms and past health. And you'll be asked about your family history.

Most children are diagnosed using an electrocardiogram (EKG). It shows the heart's electrical activity as line tracings on paper. Children with LQTS have a certain pattern to their heartbeat. The doctor can see the pattern on the tracing.

The doctor may want to do other tests too, such as a test to measure your child's heartbeat during exercise. Or the doctor may ask your child to wear a small device at home. This device measures your child's heartbeat during regular activity outside of the doctor's office.

A test may also be done to see if your child carries the gene that causes LQTS. Your child's close relatives may also get tests. Not everyone with the gene will have symptoms.

Caring for yourself when you have long QT syndrome (LQTS)

There are things you can do to help prevent a dangerous heart rhythm from LQTS.

  • Tell all of your doctors and your pharmacist about your condition.

    They can help you avoid medicines that can start a fast or abnormal heartbeat.

  • Ask your doctor for a list of over-the-counter medicines that you shouldn't take.

    These include some common medicines, such as certain antacids and antihistamines. They can trigger abnormal heartbeats in people with LQTS.

  • Talk to your doctor about whether lifestyle changes are a good idea for you.

    Some people with LQTS may need to avoid loud noises, such as alarm clocks and loud ringtones.

  • Ask your doctor about safe levels of activity.

    Most people with LQTS should avoid intense physical activity. Talk to your doctor about what type of activity and exercise is safe for you.

How does long QT syndrome (LQTS) affect your child's ability to be active?

Most children with LQTS should avoid intense physical activity. This may affect what type of exercise they can do, or whether they can take part in certain sports. Ask your doctor what type of activity is safe for your child.

What is long QT syndrome (LQTS)?

Long QT syndrome (LQTS) is a rare problem that affects the heart's electrical system. It may cause the heart to beat in a fast and abnormal way. This can cause fainting, seizures, or abnormal heartbeats that can become life-threatening. If the heart stops pumping blood, sudden death can happen.

What causes long QT syndrome (LQTS)?

LQTS can have different causes. One cause is a genetic problem that is passed down in a family. It also can be caused by a medicine or by a mineral imbalance in the blood.

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The content above contains general health information provided by Healthwise, Incorporated, and reviewed by its medical experts. This content should not replace the advice of your healthcare provider. Not all treatments or services described are offered as services by us. For recommended treatments, please consult your healthcare provider.

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