Yakup Ergül1, Hasan Candaş Kafalı1, Erman Cilsal1, Bekir Yükçü1, İbrahim Yaman2, Filiz Çetinkaya Işık2, Alper Güzeltaş1, Mehmet Ertürk3. 1. Department of Pediatric Cardiology, University of Health Sciences İstanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Training and Research Hospital, İstanbul, Turkey. 2. Department of Nursing, University of Health Sciences İstanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Training and Research Hospital, İstanbul, Turkey. 3. Chief of Hospital, University of Health Sciences İstanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Training and Research Hospital, İstanbul, Turkey.
Abstract
OBJECTIVE: Long QT syndrome (LQTS) is an inherited cardiac ion channel disorder (channelopathy) that is characterized by prolonged QT intervals on the electrocardiography (ECG) and possess the risk of sudden cardiac death (SCD). Jervell-Lange Nielsen syndrome (JLNS) is a specific subtype of LQTS that is accompanied by congenital sensorineural hearing loss, inherited autosomal recessively, and higher risk of SCD. In this study, we aimed to investigate JLNS prevalence in deaf children attending special schools for hearing loss, located in our province. METHODS: An ECG screening program was conducted in 6 special schools for children with hearing loss in İstanbul and a total of 440 students between 6 and 18 years old were included. Corrected QT interval (QTc) was calculated using the Bazett formula. Notably, 51 students, detected with any abnormal finding on ECG, were invited to our center for a comprehensive examination. RESULTS: A total of 8 patients were found with a prolonged QT interval. JLNS was diagnosed in 4 (0.9%) patients. In addition, 2 students had already been diagnosed with JLNS at another center earlier. The other 2 students, being siblings, were newly diagnosed with JLNS; and appropriate treatment was initiated. Genetic testing revealed a pathological homozygous mutation in KCNQ1 gene. The younger sibling (Case 1), who possessed a QTc of greater than 500 ms and a history of syncope, which was very suspicious for SCD, was implanted an implantable cardioverter-defibrillator. Propranolol treatment was initiated for both siblings. CONCLUSION: JLNS should be carefully considered and screened, especially in patients with a history of congenital deafness.
OBJECTIVE: Long QT syndrome (LQTS) is an inherited cardiac ion channel disorder (channelopathy) that is characterized by prolonged QT intervals on the electrocardiography (ECG) and possess the risk of sudden cardiac death (SCD). Jervell-Lange Nielsen syndrome (JLNS) is a specific subtype of LQTS that is accompanied by congenital sensorineural hearing loss, inherited autosomal recessively, and higher risk of SCD. In this study, we aimed to investigate JLNS prevalence in deaf children attending special schools for hearing loss, located in our province. METHODS: An ECG screening program was conducted in 6 special schools for children with hearing loss in İstanbul and a total of 440 students between 6 and 18 years old were included. Corrected QT interval (QTc) was calculated using the Bazett formula. Notably, 51 students, detected with any abnormal finding on ECG, were invited to our center for a comprehensive examination. RESULTS: A total of 8 patients were found with a prolonged QT interval. JLNS was diagnosed in 4 (0.9%) patients. In addition, 2 students had already been diagnosed with JLNS at another center earlier. The other 2 students, being siblings, were newly diagnosed with JLNS; and appropriate treatment was initiated. Genetic testing revealed a pathological homozygous mutation in KCNQ1 gene. The younger sibling (Case 1), who possessed a QTc of greater than 500 ms and a history of syncope, which was very suspicious for SCD, was implanted an implantable cardioverter-defibrillator. Propranolol treatment was initiated for both siblings. CONCLUSION: JLNS should be carefully considered and screened, especially in patients with a history of congenital deafness.