We Only Find What We Look For: Fetal Heart Rate and the Diagnosis of Long-QT Syndrome

Long QT syndrome (LQTS), an inherited channelopathy, is a common cause of arrhythmic death in infants, children and young adults. Although many LQTS genes have been identified, most (~75%) of LQTS mutations are found in KCNQ1, KCNH2 or SCN5A. In most cases, treatment for LQTS is successful and modifies the risk of life-threatening arrhythmias; thus, making the correct diagnosis is important. The diagnosis of LQTS is made by the measurement of a prolonged QT interval on the standard ECG; family history or characteristic arrhythmia features are used to strengthen the diagnosis and genetic testing confirms the diagnosis.