Referenced in: none

Automatically associated channels: Nav1.5

Title: SCN5A mutations in Brugada syndrome are associated with increased cardiac dimensions and reduced contractility.

Authors: Frans van Hoorn, Maria E Campian, Anje Spijkerboer, Marieke T Blom, R Nils Planken, Albert C van Rossum, Jacques M T de Bakker, Arthur A M Wilde, Maarten Groenink, Hanno L Tan

Journal, date & volume: PLoS ONE, 2012 , 7, e42037

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/22876298

Abstract
The cardiac sodium channel (Na(v)1.5) controls cardiac excitability. Accordingly, SCN5A mutations that result in loss-of-function of Na(v)1.5 are associated with various inherited arrhythmia syndromes that revolve around reduced cardiac excitability, most notably Brugada syndrome (BrS). Experimental studies have indicated that Na(v)1.5 interacts with the cytoskeleton and may also be involved in maintaining structural integrity of the heart. We aimed to determine whether clinical evidence may be obtained that Na(v)1.5 is involved in maintaining cardiac structural integrity.Using cardiac magnetic resonance (CMR) imaging, we compared right ventricular (RV) and left ventricular (LV) dimensions and ejection fractions between 40 BrS patients with SCN5A mutations (SCN5a-mut-positive) and 98 BrS patients without SCN5A mutations (SCN5a-mut-negative). We also studied 18 age/sex-matched healthy volunteers.SCN5a-mut-positive patients had significantly larger end-diastolic and end-systolic RV and LV volumes, and lower LV ejection fractions, than SCN5a-mut-negative patients or volunteers.Loss-of-function SCN5A mutations are associated with dilatation and impairment in contractile function of both ventricles that can be detected by CMR analysis.