Congenital long-QT syndrome in type 1 diabetes: a unique association

Abstract

In contrast to acquired long QT syndrome (LQTS), congenital LQTS is arelatively rare channelopathy with an incidence of 1/2,500. We describe apatient found to have a prolonged QTc in the setting of newly diagnosed Type1 DM. To the best of our knowledge, this unique association has not beenpreviously reported. Currently, it is shown that glucose ingestion aggravatedcardiac repolarization disturbances in LQT2 patients and prolonged thecardiac repolarization phase in healthy controls. Our case presented to thehospital with syncope after increased glucose level. Therefore, it seems thatincreased glucose level may have prolonged QTc interval and aggravatedcardiac repolarization disturbances in the presented case. By this report, wewant to emphasize the importance of hyperglycaemia in congenital LQTS.