[SCD-FORUM] 151E Brugada syndrome and LQTS Dr. Antzelevitch

[SCD Symposium]

In reply to Dr. Cowan:
Loss of function of sodium channel activity secondary to SCN5A mutations can accentuate the action potential notch in right ventricular epicardium, thus leading to a prolongation of the RV action potential (RVOT).  This results in an accentuation of the J wave (ST segment elevation), inversion of the T wave and prolongation of the QT interval in the right precordial leads (usually most prominent in lead V2). Keep in mind that SCN5A mutations only account for approximately 15% of BrS probands. Other gene mutations can result in more dramatic and more global changes in the QT interval. At the upcoming AHA meeting (late-breaking abstracts) we will present two new genes associated with a Brugada phenotype.  Mutations in these genes not only produce an ST segment elevation as well as abbreviation of the QT interval in all leads, in some cases approximating intervals observed in the Short QT Syndrome. The result is a clinical entity that combines BrS and SQTS.  
I hope this is helpful.
Charlie Antzelevitch 

_____________________________________
Charles Antzelevitch, PhD, FACC, FAHA, FHRS
Executive Director/Director of Research
Gordon K. Moe Scholar
Professor of Pharmacology
Masonic Medical Research Laboratory 
2150 Bleecker Street
Utica, NY 13501-1787 
Tel: (315) 735-2217 ext. 117  (after 5 PM ext. 129)
Fax: (315) 735-5648
ca at mmrl.edu
www.mmrl.edu