The genetics of cardiac arrhythmias.

Cardiac rhythm problems result in high levels of morbidity and mortality, with sudden arrhythmic death claiming approximately 300,000 lives in the United States each year. Investigations into the genetic contributions to rhythm and conduction disorders have found genes or loci associated with primary rhythm/conduction disorders such as familial atrial fibrillation and atrio-ventricular block, underscoring the importance of collecting a thorough family history. Combinations of single or multiple genes and environmental risk factors may place only certain family members at risk. Some cardiac muscle problems, such as cardiomyopathy, predispose to arrhythmia and have documented genetic components. Primary health care providers need current knowledge of genetic contributions to rhythm/conduction problems so that family members at risk can be identified early and cared for appropriately. This article provides an overview of the genetic contributions to cardiac rhythm and conduction problems.