Follow up of a family with asymptomatic compound long QT syndrome mutations.

Long QT syndromes (LQTS) are a cause of syncope and sudden death and present as a long QT interval on the surface ECG. The mortality of the condition may be quite variable among affected individuals. Hundreds of mutations in more than ten genes are identified as responsible for almost all patients with LQTS. Compound mutations are reported in different series as 4.5 and 7.9% and are associated with poor outcome. Beta blockers are the mainstay of therapy. The use of intracardiac defibrillators (ICD) is widely considered in patients at high risk for sudden death. Herein, we report a case of LQTS with compound mutations of KCNQ1 and SCN5a. Although ICD implantation was advised due to high cardiac event risk, the patient followed with beta blocker treatment for 15 years without any syncope or palpitations.