Compositions, polynucleotides, probes, kits, methods, computer systems, treatment methods and genetic markers useful for assessing the risk of Sudden Cardiac Death (SCD), Sudden Cardiac Arrest (SCA), Ventricular Arrhythmia (VA), or Heart Failure (HF) are provided herein. The compositions, polynucleotides, probes, kits, methods, computer systems, treatment methods and genetic markers of the invention can provide patients selection for those that can be treated with an ICD or CRT-D based on assessing the presence of one or more Single Nucleotide Polymorphisms (SNPs) associated with any one of Sudden Cardiac Death (SCD), Sudden Cardiac Arrest (SCA), Ventricular Arrhythmia (VA), or Heart Failure (HF), and can indicate treatment with certain drugs such as beta-blockers.