Long QT syndrome | Better Health Channel
Tell us what you think by taking our online survey
Close survey

Summary

Long QT syndrome is a cause of sudden death in children and young adults. It is caused by a fault in the electrical system of the heart which makes the heart develop an arrhythmia (beat too fast). The most common symptoms are fainting or sudden death. If you faint for any unexplained reason you should be tested for long QT syndrome with an electrocardiograph (ECG).

Long QT syndrome is a relatively common cause of sudden death in children and young adults. Long QT syndrome is diagnosed by electrocardiograph (ECG). Fainting can be a symptom of Long QT syndrome and is sometimes mistaken for a seizure. About one-third of people who have Long QT syndrome do not have any symptoms.

Warning signs of long QT syndrome


You should be investigated for Long QT syndrome if:
  • You faint for no apparent reason
  • You faint during or shortly after exercise or emotional excitement
  • There is a family history of unexplained fainting or sudden death in your family.

An inherited condition


There are two types of inherited Long QT syndrome:
  • Romano-Ward type - this is being recognised with increasing frequency. Researchers have found six genes that cause Long QT syndrome. When all the genes have been found, genetic testing for the syndrome will be possible.
  • Jervell, Lange-Nielson type - this form is rare and also causes deafness.

Acquired Long QT syndrome


Long QT syndrome can also be acquired by taking certain over-the-counter medications and some prescribed medications. If you have Long QT syndrome, always tell your doctor before they give you a prescription. There is an updated list of medications to avoid: Center for Education and Research on Therapeutics.

Exercise, noise or stress can trigger an event


An event can be triggered by:
  • Exercise
  • Being startled by a loud noise, such as a horn, ringing telephone or alarm clock
  • Exams, test or other stressful situations
  • Anger or crying.

Treatment for Long QT syndrome


Treatment includes:
  • Medications - beta blockers are effective for 90 per cent of people with Long QT syndrome.
  • Pacemaker - you may need a pacemaker or defibrillator as well as beta blocker medication.

Where to get help

  • Your doctor should refer you to a knowledgeable cardiologist
  • Royal Children’s Hospital Melbourne, Cardiology Department
  • SADS (Sudden Arrhythmic Death Syndrome) Australia

Things to remember

  • If you are diagnosed with Long QT syndrome your entire family should be tested including extended relatives.
  • Long QT syndrome is usually inherited although it can be acquired after taking certain medications.
You might also be interested in: Want to know more?

Go to More information for support groups, related links and references.
This page has been produced in consultation with and approved by:

Genetic Health Services Victoria Murdoch Childrens Research Institute

(Logo links to further information)
Genetic Health Services Victoria

Last reviewed: June 2011

Content on this website is provided for education and information purposes only. Information about a therapy, service, product or treatment does not imply endorsement and is not intended to replace advice from your doctor or other registered health professional. Content has been prepared for Victorian residents and wider Australian audiences, and was accurate at the time of publication. Readers should note that, over time, currency and completeness of the information may change. All users are urged to always seek advice from a registered health care professional for diagnosis and answers to their medical questions.


If you would like to link to this fact sheet on your website, simply copy the code below and add it to your page:

<a href="http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Long_QT_syndrome?open">Long QT syndrome - Better Health Channel</a><br/>
Long QT syndrome is a cause of sudden death in children and young adults. It is caused by a fault in the electrical system of the heart which makes the heart develop an arrhythmia (beat too fast). The most common symptoms are fainting or sudden death. If you faint for any unexplained reason you should be tested for long QT syndrome with an electrocardiograph (ECG).

Content on this website is provided for education and information purposes only. Information about a therapy, service, product or treatment does not imply endorsement and is not intended to replace advice from your qualified health professional. Content has been prepared for Victorian residence and wider Australian audiences, and was accurate at the time of publication. Readers should note that over time currency and completeness of the information may change. All users are urged to always seek advice from a qualified health care professional for diagnosis and answers to their medical questions.

For the latest updates and more information, visit www.betterhealth.vic.gov.au

Copyight © 1999/2012  State of Victoria. Reproduced from the Better Health Channel (www.betterhealth.vic.gov.au) at no cost with permission of the Victorian Minister for Health. Unauthorised reproduction and other uses comprised in the copyright are prohibited without permission.