Genetic Arrhythmias (Channelopathies)

‘Genetic arrhythmias' or ‘channelopathies' (long QT syndrome, short QT syndrome, Brugada syndrome and catecholaminergic polymorphic ventricular tachycardia) are inheritable disorders caused by mutations in genes coding for channel proteins that regulate the electrical function of the heart. These mutations favor the onset of life-threatening ventricular arrhythmias either by altering the balance of ionic currents in the cardiac action potential or by impairing the process of electromechanical coupling in cardiomyocytes. Channelopathies are lethal disorders, accounting for about one quarter of sudden cardiac deaths in young individuals with a morphologically ‘normal' autopsy. Every time a channelopathy is identified in a patient, other individuals in his/her family might be at risk of cardiac events. If a timely diagnosis is made, however, simple and efficacious preventative measures may be applied. Genetic studies play a pivotal role in the diagnosis of channelopathies and may help in the management of patients and their relatives.