AHA Scientific Statement

Vascular dysfunction is causally contributing to many dis-eases, including but not limited to cardiovascular disease, which is still the leading cause of death in the Western world. The endothelium that lines the inner wall of the blood vessels plays a critical role in the pathobiology of these illnesses. Particularly after ischemia or injury, the growth of new blood vessels, driven by endothelial expansion, is essential to maintain oxygen supply to the ischemic or injured tissue. Recent studies additionally sug-gest that the endothelium acts as a paracrine source for signals that determine tissue regeneration versus fibrosis after injury. Excessive vascularization, however, might also be unwanted, as in the case of cancer, neovascular eye diseases including diabetic retinopathy, atheroma growth, or the expansion of vasa vasorum, which leads to adverse vessel wall remodeling. Neovascularization is a tightly regulated and essential process that results in the formation of new blood vessels