Sleep Research Study for Long QT Syndrome Patients

Why are we doing this research?

The congenital long QT syndrome (LQTS) is a heart disease that tends to occur among family members.  LQTS patients are at increased risk of sudden cardiac (heart) death.  There are three major subtypes, LQT1, LQT2 and LQT3.  About 97% cardiac events in LQT1 patients are related to exercise, emotional stress or swimming.  In contrast, individuals with LQT2 and LQT3 are especially at risk during sleep, about 29% for LQT2 and 39% for LQT3.  Our research is aimed at understanding why LQT2 and LQT3 patients develop heart problems during sleep.

Who can participate?

Children and adults aged 5 years and older with LQTS may be able to participate in this research study.


  • Adult Studies
  • Cardiology - Heart
  • Sleep

What will happen in the study?

This study lasts for 18 hours and includes single visit. The following is a list of procedures that will take place during the study:

  • Questionnaires
  • Blood tests
  • Electrocardiogram (ECG) and blood pressure measurements
  • Sleep measurements
  • Breathing tests

What are the good things that can happen from this research?

If you agree to allow your child to take part in this research study, your child may not receive a direct medical benefit.  The information learned from this research study may benefit other patients with congenital long QT syndrome in the future.  Clinical studies are essential in finding new and improved treatments and diagnostic tools. 

Will I get all the facts about the study?

Parents will be given a consent form that thoroughly explains all of the details of the study.  The consent form includes all of the procedures, the risks, the benefits, the compensation, who to contact with questions or concerns, and more.  A member of the study staff will review the consent form with you and will be sure that all of your questions are answered.  Study procedures will not begin until the parent or guardian have signed this form and, if of age, the child has given at minimum his/her verbal agreement. 

What are the bad things that can happen from this research?

More extensive information about study risks and procedures will be given before study participation begins.
Questionnaires: These are short sets of questions about your child’s health, exercise and sleep that will take about 30 minutes to answer.  It will be explained to your child that there are no wrong answers.  They may choose not to answer any questions that are uncomfortable to them.

Blood Samples: The risks of drawing blood include minor pain, bruising, or rarely, infection at the site of the needle stick.  A numbing cream is used on the skin to make this as comfortable as possible.

Electrocardiogram (ECG) and Blood Pressure Measurements: With blood pressure measurements, inflation of the cuff can cause temporary discomfort from tightness. The fingers and hand can sometimes feel cold and tingly while the cuff is tight. Rarely, there can be redness or a bruise from the cuff.
With the ECG, there can occasionally be redness to the skin from the bandage-like patches.

Sleep Measurements: The sleep patches for the overnight sleep study are attached with paste and tape and may cause some irritation of the skin.  Sleeping overnight away from home can be distressing for some children and sleeping with the monitors attached to your child’s skin may make your child uncomfortable or wake your child up during the night. However, you or another family member will sleep in the same room so your child will not be alone during the sleep study. You will be able to see all of the sleep study procedures.

Apnea and Paced breathing: Paced breathing may cause your child to be lightheaded.  If so he/she will be asked to decrease the rate and depth of breathing.  The breath holds may be uncomfortable.  There is a small possibility that this may cause slowing of your child’s heart rate. 


Contact Us.Abu Shamsuzzaman, MD