Proarrhythmogenic Effect of the L532P and N588K KCNH2 Mutations in the Human Heart Using a 3D Electrophysiological Model

J Korean Med Sci. 2020 Jul 27;35(29):e238. doi: 10.3346/jkms.2020.35.e238.

Abstract

Background: Atrial arrhythmia is a cardiac disorder caused by abnormal electrical signaling and transmission, which can result in atrial fibrillation and eventual death. Genetic defects in ion channels can cause myocardial repolarization disorders. Arrhythmia-associated gene mutations, including KCNH2 gene mutations, which are one of the most common genetic disorders, have been reported. This mutation causes abnormal QT intervals by a gain of function in the rapid delayed rectifier potassium channel (IKr). In this study, we demonstrated that mutations in the KCNH2 gene cause atrial arrhythmia.

Methods: The N588K and L532P mutations were induced in the Courtemanche-Ramirez-Nattel (CRN) cell model, which was subjected to two-dimensional and three-dimensional simulations to compare the electrical conduction patterns of the wild-type and mutant-type genes.

Results: In contrast to the early self-termination of the wild-type conduction waveforms, the conduction waveform of the mutant-type retained the reentrant wave (N588K) and caused a spiral break-up, resulting in irregular wave generation (L532P).

Conclusion: The present study confirmed that the KCNH2 gene mutation increases the vulnerability of the atrial tissue for arrhythmia.

Keywords: KCNH2 Gene Mutation; L532P Mutation; N588K Mutation; Three-dimensional Heart Modeling.

MeSH terms

  • Action Potentials
  • Arrhythmias, Cardiac / genetics
  • Arrhythmias, Cardiac / pathology*
  • ERG1 Potassium Channel / genetics*
  • Heart / physiology
  • Humans
  • Imaging, Three-Dimensional
  • Models, Cardiovascular*
  • Polymorphism, Single Nucleotide

Substances

  • ERG1 Potassium Channel
  • KCNH2 protein, human