Two critical events in the development of the vascular system: pruning and remodeling.

The cardiovascular system is the first functional organ system to develop in the vertebrate embryo. The primitive heart and primitive vascular plexus are formed through vasculogenesis and thereafter through angiogenesis. After the establishment of new connections within the vascular network, a pruning and remodeling process occurs after which some branches are stabilized, whereas others regress. The aim of this article is to describe the most common pruning and remodeling forms, which take place during organogenesis in the experimental and human systems.