Long QT syndrome usually lasts a lifetime. The risk of an irregular heartbeat leading to fainting or sudden cardiac arrest may decrease with age but never completely disappear. There are several important things you need to do for the rest of your life to prevent an abnormal heart rhythm.

Some people with drug-induced LQTS may also have another genetic disorder. They may not have symptoms unless they are taking drugs that prolong the QT interval or reduce potassium levels in the blood. When LQTS does not cause symptoms, it is called silent LQTS.

Long QT syndrome is a disorder of the heart's electrical system. Torsade de pointes (TdP), as indicated on the electrocardiogram (ECG), is a feature of ventricular hyperrhythmias that present complex torsades de pointes. The QT interval is the upper part of the electrocardiogram, representing the time it takes for the electrical system to fire impulses through the ventricles and then recharge.