Sex hormones and cardiac arrest in long QT syndrome: Does progesterone represent a potential new antiarrhythmic therapy?

Abstract

In adult patients with congenital long QT syndrome (LQTS) type 1 and type 2, female gender is associated with a higher risk for polymorphic ventricular tachycardia (pVT) and sudden cardiac death (SCD). 1 Zareba W. Moss A.J. Locati E.H. et al. International Long QT Syndrome RegistryModulating effects of age and gender on the clinical course of long QT syndrome by genotype. J Am Coll Cardiol. 2003; 42: 103-109 Abstract Full Text Full Text PDF PubMed Scopus (230) Google Scholar , 2 Sauer A.J. Moss A.J. McNitt S. et al. Long QT syndrome in adults. J Am Coll Cardiol. 2007; 49: 329-337 Abstract Full Text Full Text PDF PubMed Scopus (305) Google Scholar Moreover, the risk for potentially lethal ventricular arrhythmias is particularly pronounced during the postpartum period, especially in patients with LQTS type 2 (LQT2). 3 Seth R. Moss A.J. McNitt S. et al. Long QT syndrome and pregnancy. J Am Coll Cardiol. 2007; 49: 1092-1098 Abstract Full Text Full Text PDF PubMed Scopus (228) Google Scholar , 4 Khositseth A. Tester D.J. Will M.L. Bell C.M. Ackerman M.J. Identification of a common genetic substrate underlying postpartum cardiac events in congenital long QT syndrome. Heart Rhythm. 2004; 1: 60-64 Abstract Full Text Full Text PDF PubMed Scopus (99) Google Scholar Notably, the arrhythmogenic risk is lower during pregnancy, 5 Rashba E.J. Zareba W. Moss A.J. et al. LQTS InvestigatorsInfluence of pregnancy on the risk for cardiac events in patients with hereditary long QT syndrome. Circulation. 1998; 97: 451-456 Crossref PubMed Scopus (194) Google Scholar indicating a potential role for sex hormones in modulating the arrhythmogenic risk in LQTS. Potential depot medroxyprogesterone acetate–triggered torsades de pointes in a case of congenital type 2 long QT syndromeHeart RhythmVol. 9Issue 7PreviewCongenital or acquired long QT syndrome (LQTS) stems from disordered myocardial repolarization and is characterized by a prolonged QT interval on an electrocardiogram and an increased risk of syncope and sudden death secondary to torsades de pointes (TdP). Female gender is an independent risk factor for the development of TdP in both forms of LQTS.1,2 Furthermore, while women with congenital LQTS have a reduced risk of TdP-triggered cardiac events during pregnancy, the 9-month postpartum period represents a temporal window of increased arrhythmogenicity. Full-Text PDF