Long QT syndrome
Arrhythmias that are not due to structural heart disease account for 5 to 10% of sudden cardiac arrests. These are frequently caused by genetic disorders that lead to abnormal heart rhythms. The genetic mutations often affect specialised proteins known as ion channels that conduct electrically charged particles across the cell membrane, and this group of conditions are therefore often referred to as channelopathies. Examples of these inherited arrhythmia syndromes include Long QT syndrome, Brugada Syndrome, Catecholaminergic polymorphic ventricular tachycardia, and Short QT syndrome. Other conditions that promote arrhythmias but are not caused by genetic mutations include Wolff-Parkinson-White syndrome.