Long QT Syndrome

Posted by e-Medical PPT Wednesday, September 8, 2010
The long QT syndrome (LQTS) is a rare inborn heart condition in which delayed repolarization of the heart following a heartbeat increases the risk of episodes of torsade de pointes.This may lead to palpitations, fainting and sudden death due to ventricular fibrillation.LQTS can arise from mutation of one of several genes.These mutations tend to prolong the duration of the ventricular action potential (APD), thus lengthening the QT interval. LQTS can be inherited in an autosomal dominant or an autosomal recessive fashion.
All forms of the long QT syndrome involve an abnormal repolarization of the heart. The abnormal repolarization causes differences in the refractory period of the myocytes.After-depolarizations can be propagated to neighboring cells due to the differences in the refractory periods, leading to re-entrant ventricular arrhythmias.
Those diagnosed with long QT syndrome are usually advised to avoid drugs that would prolong the QT interval further.Administration of beta receptor blocking agents which decreases the risk of stress induced arrhythmias. Beta blockers are the first choice in treating Long QT syndrome.The effective form of arrhythmia termination in individuals with LQTS is placement of an implantable cardioverter-defibrillator (ICD). Alternatively, external defibrillation can be used to restore sinus rhythm.ICDs are commonly used in patients with syncopes despite beta blocker therapy, and in patients who have experienced a cardiac arrest.

Related Posts Plugin for WordPress, Blogger...

0 Responses to Long QT Syndrome

Post a Comment

Share This

GET UPDATES!!!

Subscribe by E-mail & receive updates your inbox!
Enter your email address:

Follow Us on Facebook

Blog Archive