Arrhythmogenic consequences of Na+ channel mutations in the transmurally heterogeneous mammalian left ventricle: analysis of the I1768V SCN5A mutation.


BACKGROUND Congenital mutations in the cardiac Na+ channel (encoded by SCN5A) underlie long QT syndrome type 3. The sea anemone peptide toxin ATX-II mimics the slowed inactivation kinetics characteristic of many long QT type 3 (LQT3) mutations. However, the I1768V SCN5A mutation is associated with faster recovery kinetics, for which there exists no known… (More)