[Inherited cardiac diseases caused by Nav1.5 sodium channel mutations].

Contraction of the heart is achieved through a delicately regulated conduction of electrical impulses. A pivotal element in the impulse propagation is the depolarising sodium current responsible for the initial depolarisation of the cardiomyocytes. Recent research has shown that mutations in the gene encoding the cardiac sodium channel (SCN5A) is associated with both rare forms of ventricular arrhythmia, and with the most frequent form of arrhythmia, atrial fibrillation.