31. Strategy for diagnosis and treatment for congenital long QT syndrome: A case report
Main Article Content
Abstract
Congenital long QT syndrome (LQTS) is an inherited cardiac channelopathy, characterized by delayed ventricular repolarization and sudden death. We report a 5-month-old boy with a family history of sudden death, fatigued despite a full night sleep, and corrected QT interval (QTc) of 548 ms on electrocardiogram. Genetic testing detected a heterozygous SCN5A mutation (NM_000335.4: c.1231G>A, NP_000326.2: p. Val411Met). He was diagnosed as LQTS type 3 and classified at high-risk group. He was treated with propranolol at an initial dose of 1 mg/kg/24h, then increased to 1.5 mg/kg/24h, combined with avoid drugs and foods that cause to delay QTc. The regimen was well tolerated and after 7 months of treatment, the patient was asymptomatic with QTc 474ms. We proved that LQTS diagnosis and treatment based on risk stratification, clinical information, electrocardiogram, and genetic testing is an effective and successful approach.
Article Details
Keywords
congenital long QT syndrome, family history of sudden death, SCN5A mutation, beta blocker, propranolol
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