Jervell-Lange-Nielsen Syndrome is a genetic condition associated with a prolonged QT interval on the ECG and congenital hearing loss.
A mutation of the cardiac potassium channel is responsible, specifically the KCNQ1 (90%) and KCNE1 (10%) genes. Jervell-Lange-Nielsen Syndrome is inherited in an autosomal recessive fashion.
Treatment includes beta-blockers. However, if syncope or sustained ventricular arrhythmias are present, an implantable cardioverter defibrillator (ICD) is indicated to prevent sudden cardiac death.