Sunday, February 05, 2006
Add one to the list of cardiac channelopathies
First there was long QT syndrome. Then in the late 80s we had Brugada syndrome. Now there’s short QT syndrome (reviewed in CMAJ). This is another must-not-miss electrocardiographic diagnosis. Three mutations have been characterized so far, all of which increase conductance through the potassium channel, thus shortening repolarization. The patients have high risk of sudden cardiac death from ventricular arrhythmias. An interesting and characteristic association is a high incidence of paroxysmal atrial fibrillation in patients or their families. The only treatment at present is device therapy, although investigations are ongoing with drugs that prolong the QT.