Long QT syndrome and life threatening arrhythmia in a newborn: molecular diagnosis and treatment response. Issue 1 (15th December 2003)

• Record Type: Journal Article
• Authors: Schulze-Bahr, E; Fenge, H; Etzrodt, D; Haverkamp, W; Mönnig, G; Wedekind, H; Breithardt, G; Kehl, H-G
• Is Part Of: Heart. Volume 90:Issue 1(2004)
• Page Start: 13
• Page End: 16
• Publication Date: 2003-12-15
• Subjects: long QT syndrome -- newborn -- propranolol -- mexiletine -- genotyping; AV, atrioventricular -- LQT3, sodium channel gene -- LQTS, long QT syndrome -- SIDS, sudden infant death syndrome; Heart -- Diseases -- Treatment -- Periodicals; Cardiology -- Periodicals; 616.12
• DOI: 10.1136/heart.90.1.13
• Languages: English
• ISSNs: 1355-6037

Abstract

Abstract : Intrauterine and neonatal manifestations of congenital long QT syndrome are associated with a high cardiac risk, particularly when atrioventricular block and excessive QT prolongation (> 600 ms 1/2 ) are present. In a female newborn with these features, treatment with propranolol and mexiletine led to complete reduction of arrhythmia that was maintained 1.5 years later. High throughput genetic analysis found a sodium channel gene (LQT3) mutation. Disappearance of the 2:1 atrioventricular block and QTc shortening (from 740 ms 1/2 to 480 ms 1/2 ), however, was achieved when mexiletine was added to propranolol. This effect was considered to be possibly genotype related. Early onset forms of long QT syndrome may benefit from advanced genotyping.