Channelopathies are a genetically conditioned group of disorders related with defects in ion channels, responsible for the occurrence of dangerous abnormal heart rhythm in a structurally normal heart. These diseases are a frequent cause of arrhythmias and sudden cardiac death, especially among the young population. The following congenital channelopathies are discussed in the presented study: long QT syndrome (LQTS), Brugada syndrome, short QT syndrome (SQTS), and catecholaminergic polymorphic ventricular tachycardia (CPVT). The symptoms most often occur during physical effort or great stress, but may also occur while resting. The diagnosis is based on medical and family history taking, ECG recording, and sometimes on genetic tests. These diseases are relatively prevalent and are characterized by high mortality. Unfortunately, the treatment remains practically exclusively symptomatic. Pharmacotherapy and implantable cardioverter-defibrilator (ICD) are used to prevent sudden cardiac death. In some centres worldwide, surgical left cardiac sympathetic denervation (LCSD) is performed in patients with contraindications for other forms of therapy.