Long QT Syndrome and Drugs

Long QT Syndrome (LQTS) is a condition that involves the electrical system of the heart. Cardiac arrest and sudden death are serious complications of the condition. This condition may be related to genetics, or may also be caused by certain drugs and other medical conditions. Many persons who have LQTS may never experience symptoms. Signs of this condition include fainting, seizures, and sudden death resulting from an abnormal heartbeat. Fainting may be triggered by exercise or startling noises.

If a drug is causing long QT syndrome, the physician may prescribe alternative medications that have not been shown to cause the long QT syndrome. When the condition is inherited, treatment may include medications, surgery, or changes in lifestyle. Treatments for long QT syndrome include beta-blocker drugs and potassium. Beta-blockers, such as nadolol (Corgard) and propranolol (Inderal), decrease the heart rate. These drugs help prevent the fast heartbeats that may be triggered by startling events or stressful situations. Potassium may also be given to decrease the QT interval. Options for persons who do not respond to drug therapy include an implantable cardioverter-defibrillator, which works to monitor for arrhythmias and to stop potentially fatal irregular heart rhythms.