Chapter 7 - Cellular and Molecular Pathobiology of the Cardiac Conduction System

Abstract

The human heart contracts approximately two billion times over the average human lifetime with little margin for error. Proper cardiac function further requires the synchronized electrical activation of the myocardium controlled by networks of specialized cardiac cells governing automaticity and cardiac impulse conduction. Over the past decade, pathologists, molecular cardiologists, geneticists, and electro-physiologists have elucidated a wealth of information regarding the structural and molecular components responsible for regulating the properties of the myocardium, as well as the systems governing the cardiac conduction system. Furthermore, we are now beginning to understand the coordinated dysregulation of these pathways in human pathophysiology. This chapter will focus on the structural and functional pathways governing cardiac conduction as well as discuss the mechanisms underlying dysfunction of the conduction system in human pathophysiology.