Cardiac channelopathies

[Julene]

Cardiac channelopathies are genetic abnormalities in heart cell proteins that control heart electrical activity and thus can cause heart rhythm disturbances.
(See also Overview of Abnormal Heart Rhythms.)
Most people who have cardiac channelopathies have no other heart disease, such as a heart attack or a heart valve disorder, but they carry mutations in the genes that determine the make-up or the regulation of heart membrane pores (channels) and are predisposed to heart rhythm abnormalities.
The most common channelopathies cause

Long QT syndrome

Other, more rare cardiac channelopathies include the following:

Short QT syndrome
J-wave syndrome
Catecholaminergic polymorphic ventricular tachycardia (CPVT)
Brugada syndrome

The electrical defects sometimes cause ventricular tachycardia, a dangerously rapid heart rhythm, or ventricular fibrillation, in which the heart does not beat at all.