A 23-year-old female had been suffering from recurrent syncopal episodes during sleep since her childhood. She had a family history of sudden death and her QTc interval was remarkably prolonged to 537 ms A Holter ECG revealed torsade de pointes, corresponding to syncope. She was started on mexiletine and her QTc interval shortened. Her symptoms were controlled after β-blockers and Ca-blockers were added. A genetic analysis with a next generation sequencer identified a frameshift mutation at the C terminus of the KCNH2 gene. Here we present a type 2 long QT syndrome case in which mexiletine was effective.
Keywords: KCNH2; long QT syndrome; mexiletine; sudden death; torsade de pointes.
© 2020 The Authors. Journal of Arrhythmia published by John Wiley & Sons Australia, Ltd on behalf of the Japanese Heart Rhythm Society.