Abstract：In cardiac ion channel diseases, there are a part of primary electrical disorders which easily lead to sudden cardiac death (SCD) in the absence of structural heart diseases, accounting for approximately 30% of young SCD patients. These electrical disorders include congenital long QT syndrome, congenital short QT syndrome, Brugada syndrome and catecholaminergic polymorphic ventricular tachycardia. These diseases usually have low penetrance and lack typical clinical manifestation, greatly challenging clinical diagnosis. However, SCD is probably the first symptom of primary cardiac ion channel diseases, and therefore it is especially important to make early diagnosis. This paper comprehensively introduces the clinical manifestations and diagnostic criteria, genetic background, pathophysiologic mechanism, and therapy of the above four kinds of primary cardiac ion channel diseases, in order to provide a clue for prevention and control of severe arrhythmias and even SCD.
