Valtimoverkko

Valtimoverkko, literally the arterial network, is the network of arteries in the circulatory system. In Finnish medical terminology it denotes the system of blood vessels that carries oxygenated blood away from the heart to tissues throughout the body, excluding the pulmonary arteries which are part of the pulmonary circulation. The systemic arterial network originates at the aorta and branches into progressively smaller arteries and arterioles that reach nearly every organ and tissue.

Structure: Arterial walls are composed of three layers: intima, media, and adventitia. Elastic arteries (for example the aorta) are rich in elastic fibers to absorb the pulsatile output of the heart; muscular arteries regulate flow via smooth muscle. Arterioles control resistance and flow into capillary beds. The network ends at capillaries where gas exchange occurs, after which blood returns via the venous network.

Function: The arterial network distributes oxygen and nutrients, removes carbon dioxide and waste, helps maintain mean arterial pressure, and adaptively distributes blood flow in response to activity and local metabolic demand via vasodilation and vasoconstriction triggered by nerves and local factors.

Clinical relevance: Arterial disease such as atherosclerosis, aneurysms, hypertension, and peripheral artery disease affect the Valtimoverkko, increasing cardiovascular risk. Age-related stiffness of large arteries and vascular remodeling can influence blood pressure and organ perfusion.