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Long Q-T Syndrome
What is it?
Long Q–T syndrome (LQTS) is a rare disorder of the heart's electrical rhythm that usually affects children or young adults. It can start at birth or later in life.
There are four chambers in the heart — the top two are the atria and the lower two are the ventricles. The heart uses a complex electrical system to get the muscle walls of the atria and ventricles to pump blood through the body.
The heartbeat is what makes the muscle walls squeeze in and relax in the right order. The heartbeat normally starts in the right atrium when a group of cells sends an electrical signal. This is the heart's pacemaker.
The signal travels on fibers to start the atria and ventricles and that completes one heartbeat.
The signal can be recorded during an electrocardiogram (ECG) test. The signal produces a pattern designated by the letters P, Q, R, S and T. The Q-T interval is the time between the start and finish of the pumping or squeeze of the ventricles.
A health care provider can measure this time and know if it takes longer than normal. If it takes longer, it's called a prolonged Q-T interval.
A child with this condition can have a heartbeat that is too quick and the heart muscle can't contract the way it should. The amount of blood to the body and brain is less than normal. If the brain doesn't get enough oxygen, a child can lose consciousness and could die without warning.
How is it treated?
Long Q-T syndrome can be treated with medicines and/or a defibrillator.