Sodium Channel Splicing in Heart Failure Trial

The purpose of this research is to see if investigators can detect truncated mRNA splice variants of the cardiac voltage-gated sodium (Na+) channel gene, SCN5A, in patients with a weak heart (Heart Failure) with or without an implantable cardioverter-defibrillator (ICD) and compare them to patients with a normal heart. Hypothesis: 1. Patients with reduced left ventricular ejection fraction have increased abundances truncated mRNA splice variants of the SCN5A gene, which portends to sodium channel dysfunction and an increased risk for sudden cardiac death. 2. Patients with implantable cardioverter-defibrillator devices (ICDs) who have experienced shock therapy have increased abundances of truncated mRNA splice variants of the SCN5A gene compared to similar congestive heart failure patients who have not experienced shock therapy.