[Sudden fainting in a young woman]

A 37-year old woman (without personal medical records) is admitted in hospital for a sudden syncope (duration 15 minutes) with postcritical condition. Her family records show the sudden death of the mother (at 39). Complementary exams do not indicate anything abnormal except a hypercholesterolemia and the electrocardiogram reveals a lengthening of the QT interval. The cardiac check-up of the family members also reveals a lengthening of the QT interval of the two patient's girls. The audiometry is normal and genetic analysis shows mutations of genes coding for a cardiac ionic canal. The diagnosis of "Romano-Ward" syndrome (syndrome of long congenital QT with dominant autosomal transmission, but without deafness) is thus retained. This syndrome as well as the other form of long congenital QT (syndrome of Jervell and Lange Nielsen with recessive autosomal transmission and deafness) are caused by mutations of genes coding for cardiac ionic canals, leading to a prolonged repolarization. The basic treatment is based on betablockers medication. A pacemaker is necessary in case of severe bradycardia, whether spontaneous or resulting from betablockers medication. An implantable cardioverter defibrillator can be a resort in refractory cases.