Epicardial and coronary vascular development
The coronary circulation is essential for human life. In embryonic development, abnormal formation of the coronary vasculature can cause death in utero or after birth. In adulthood, atherosclerosis of the coronary arteries is the commonest cause of death worldwide. The last decade has witnessed significant strides forward in our understanding of coronary development. Multiple sources of coronary endothelial cells have been identified using genetic tools for fate mapping. The epicardium, the outermost layer of the developing heart, has emerged as both a source of cell progenitors and key signalling mediators. Knowledge of the specific genes underlying formation, function, and heterogeneity of the epicardium is expanding. Significant challenges remain, however, in understanding the spatiotemporal signalling patterns required for organized migration, differentiation, and patterning of the vasculature. In addition, dissecting how coronary development is perturbed in patients with congenital coronary anomalies is a major ongoing focus of research.