UMEM Educational Pearls

 

Despite advancement of molecular genetics dx of congenital long QT syndrome is based on ECG & clinical characteristics
Typical presentation is that a child/young adult experienced unexplained syncope or sudden death during physical exertion or emotional agitation
Bazett formula (QTc = QT x RR 1/2) is the most widely used method for measuring QTc
A QTc interval longer than 440 ms has been considered prolonged
1st described was QT prolongation w/congenital bilateral neural deafness and SCD (Jervell and Lange-Nielsen syndrome)
The more common form is QT prolongation w/o deafness and SCD (Romano-Ward syndrome)
Beta-blockers remain the mainstay treatment
Implantable cardioverter-defibrillator (ICD) is an effective therapeutic option to reduce mortality

References

Congenital and Acquired Long QT Syndrome.Cardiology in Review. 12(4):222-34, 2004 Jul-Aug