Mikael Koponen1, Annukka Marjamaa2, Anita Hiippala2, Juha-Matti Happonen2, Aki S Havulinna2, Veikko Salomaa2, Annukka M Lahtinen2, Taina Hintsa2, Matti Viitasalo2, Lauri Toivonen2, Kimmo Kontula2, Heikki Swan2. 1. From the Heart and Lung Center, Helsinki University Central Hospital (M.K., A.M., M.V., L.T., H.S.), Children's Hospital, Helsinki University Central Hospital (A.H., J.-M.H.), Department of Medicine, Helsinki University Central Hospital (A.M.L., K.K.), and Institute of Behavioural Sciences, Psychology (T.H.), University of Helsinki, Helsinki, Finland; and Department of Health, National Institute for Health and Welfare, Helsinki, Finland (A.S.H., V.S.). mikael.koponen@helsinki.fi. 2. From the Heart and Lung Center, Helsinki University Central Hospital (M.K., A.M., M.V., L.T., H.S.), Children's Hospital, Helsinki University Central Hospital (A.H., J.-M.H.), Department of Medicine, Helsinki University Central Hospital (A.M.L., K.K.), and Institute of Behavioural Sciences, Psychology (T.H.), University of Helsinki, Helsinki, Finland; and Department of Health, National Institute for Health and Welfare, Helsinki, Finland (A.S.H., V.S.).
Abstract
BACKGROUND: Inherited long-QT syndrome (LQTS) is associated with risk of sudden death. We assessed the clinical course and the fulfillment of current treatment strategies in molecularly defined pediatric LQTS type 1 and (LQT1) and type 2 (LQT2) patients. METHODS AND RESULTS: Follow-up data covering a mean of 12 years were collected for 316 genotyped LQT1 and LQT2 patients aged 0 to 18 years. No arrhythmic deaths occurred during the follow-up. Finnish KCNQ1 and KCNH2 founder mutations were associated with fewer cardiac events than other KCNQ1 and KCNH2 mutations (hazard ratio [HR], 0.33; P=0.03 and HR, 0.16; P=0.01, respectively). QTc interval ≥500 ms increased the risk of cardiac events compared with QTc <470 ms (HR, 3.32; P=0.001). Treatment with β-blocker medication was associated with reduced risk of first cardiac event (HR, 0.23; P=0.001). Noncompliant LQT2 patients were more often symptomatic than compliant LQT2 patients (18% and 0%, respectively; P=0.03). Treatment with implantable cardioverter defibrillator was rare (3%) and resulted in reinterventions in 44% of cases. CONCLUSIONS: Severe cardiac events are uncommon in molecularly defined and appropriately treated pediatric LQTS mutation carriers. β-Blocker medication reduces the risk of cardiac events and is generally well tolerated in this age group of LQTS patients.
BACKGROUND: Inherited long-QT syndrome (LQTS) is associated with risk of sudden death. We assessed the clinical course and the fulfillment of current treatment strategies in molecularly defined pediatric LQTS type 1 and (LQT1) and type 2 (LQT2) patients. METHODS AND RESULTS: Follow-up data covering a mean of 12 years were collected for 316 genotyped LQT1 and LQT2patients aged 0 to 18 years. No arrhythmic deaths occurred during the follow-up. Finnish KCNQ1 and KCNH2 founder mutations were associated with fewer cardiac events than other KCNQ1 and KCNH2 mutations (hazard ratio [HR], 0.33; P=0.03 and HR, 0.16; P=0.01, respectively). QTc interval ≥500 ms increased the risk of cardiac events compared with QTc <470 ms (HR, 3.32; P=0.001). Treatment with β-blocker medication was associated with reduced risk of first cardiac event (HR, 0.23; P=0.001). Noncompliant LQT2patients were more often symptomatic than compliant LQT2patients (18% and 0%, respectively; P=0.03). Treatment with implantable cardioverter defibrillator was rare (3%) and resulted in reinterventions in 44% of cases. CONCLUSIONS: Severe cardiac events are uncommon in molecularly defined and appropriately treated pediatric LQTS mutation carriers. β-Blocker medication reduces the risk of cardiac events and is generally well tolerated in this age group of LQTS patients.
Authors: Kyung Jin Ahn; Mi Kyoung Song; Sang Yun Lee; Ja Kyoung Yoon; Gi Beom Kim; Seil Oh; Eun Jung Bae Journal: Korean Circ J Date: 2022-10 Impact factor: 3.101
Authors: Mikael Koponen; Aki S Havulinna; Annukka Marjamaa; Annukka M Tuiskula; Veikko Salomaa; Päivi J Laitinen-Forsblom; Kirsi Piippo; Lauri Toivonen; Kimmo Kontula; Matti Viitasalo; Heikki Swan Journal: BMC Med Genet Date: 2018-04-05 Impact factor: 2.103
Authors: Heta Huttunen; Matti Hero; Mitja Lääperi; Johanna Känsäkoski; Heikki Swan; Joel A Hirsch; Päivi J Miettinen; Taneli Raivio Journal: Front Endocrinol (Lausanne) Date: 2018-04-24 Impact factor: 5.555