Inherited cardiac transmembrane channel diseases are caused by the dysfunction of ion channels in the heart. The disorder can manifest itself at the level of sodium, potassium or calcium channels. The clinical presentation may vary in a wider range from completely asymptomatic to sudden cardiac death. Almost 10% of all sudden cardiac deaths are caused by one of inherited cardiac transmembrane channel diseases. Identifying asymptomatic patients before the onset of symptoms is a key step in the prevention of fatal outcome, since it usually affects young, seemingly healthy, population. In the group of inherited cardiac transmembrane channel diseases we include long QT syndrome (LQTS), short QT syndrome (SQTS), Brugada syndrome (BRS), catecholaminergic polymorphic ventricular tachycardia (CPVT) and early repolarization syndrome (ERS). This group of diseases has attracted great attention of specialists in recent years and have made significant progress in their diagnosis, risk stratification and treatment options. Although individually rare, together they form a sizeable group of diseases with potentially lethal outcome, which is why there is a great need for further research and the adoption of uniform guidelines in this area.