The idea that someone could have a life-threatening heart condition and not know it is frightening. Worse is the idea that this disease could strike without warning. However, anyone may be walking around with long QT syndrome and never know they are in danger—until it's too late.
Long QT syndrome is a fairly rare heart condition, affecting about 1 in 6,000 people. Some people may never experience any symptoms, and only those with a family history of long QT syndrome are likely to have undergone a simple test to detect the condition before symptoms hit.
While two-thirds of all patients with long QT syndrome have a genetically inherited form of the disease, there are about 50 medications, such as some antidepressants, antibiotics, antihistamines and cholesterol-lowering drugs, that are known to cause the condition in otherwise "healthy" people. Patients who have been diagnosed with this condition should avoid taking these drugs altogether and should ask their doctor about any new drugs they are prescribed.
A Heart's Short Circuit
Long QT syndrome is a problem in the heart's electrical wiring. As the heart pumps blood, it coordinates the contraction of the upper and lower chambers through electrical impulses. After every heartbeat, your electrical system needs to recharge. If you have long QT syndrome, your heart takes longer to recharge than a normal heart. An electrocardiogram (ECG), which charts the electrical activity in your heart by dividing the electrical waves into intervals, can detect this electrical disturbance as an increase in time between the Q and T waves—thus, the name long QT syndrome. The lapse in heartbeat can cause an arrhythmia, an irregular beat, which leads to reduced blood flow to the rest of the body, especially the brain, where it causes the most serious problems.
The most common warning sign of long QT syndrome is fainting. However, seizures and sudden death may also be the first sign that you have this condition. A person with the condition may faint and lose consciousness during exercise or extreme emotional excitement or when startled or scared.
What Can You Do?
If you or your child faint for no other known reason, or it happens often, be sure to see a doctor. After a simple ECG, your doctor can usually make a diagnosis. The good news is that treatment for long QT syndrome is fairly effective; beta-blockers can prevent fainting episodes in 90 percent of patients. Occasionally potassium, which helps to stabilize electrical activity to the heart, is also given to patients to help shorten the prolonged QT interval. Your doctor may recommend switching some of the medications you are currently taking if they increase your risk for prolonging your QT interval.
It's frightening to think that you may be walking around with a serious condition and not even know it, but if you do experience a warning sign, be sure to follow up—it could save your life.
