Coronary Arteriogenesis and Differentiation of Periarterial Purkinje Fibers in the Chick Heart

In the following review, we outline the cellular ontogeny and time course of coronary artery development within the vertebrate heart. Our eventual focus will be the potential role of arteriogenesis in the differentiation of a subset of specialized conduction cells in the chick heart. We begin by briefly outlining early heart formation, showing how the outermost layer of the looped, tube heart—the epicardium—is of extracardiac origin and provides the progenitor cells to the entire vascular bed. Subsequently, we summarize the events of coronary arterial development that follow epicardialization. Finally, we discuss work in the chick that indicates how arteries form pioneering, directional conduits through ventricular tissue, adjacent to which myocardial cells differentiate to form the most peripheral component of the avian conduction system—a network of periarterial Purkinje fibers. (Tex Heart Inst J 2002;29:262–70)