valtimotasi

Valtimotasi, or arterial tone in English, is the level of baseline constriction or dilation of arterial smooth muscle that determines systemic vascular resistance and, consequently, blood pressure and organ perfusion.

It is regulated by a balance between vasoconstrictor and vasodilator influences, including the autonomic nervous system, endothelial signaling, and circulating hormones. Sympathetic nerves release norepinephrine that acts on alpha-adrenergic receptors to increase tone, while baroreceptors and chemoreceptors adjust tone to maintain blood pressure.

Endothelial cells produce nitric oxide and endothelin, promoting vasodilation and vasoconstriction, respectively. The renin-angiotensin-aldosterone system, prostaglandins, and metabolites like adenosine influence tone locally.

Clinical relevance: Abnormally high valtimotasi over time contributes to hypertension and increased cardiac afterload; abnormally low tone may cause hypotension and inadequate tissue perfusion. Conditions such as pheochromocytoma, sepsis, or autonomic dysfunction may alter arterial tone.

Assessment and management: Direct measurement of arterial tone is rarely performed in routine care; systemic vascular resistance can be estimated. Treatment aims to normalize tone with lifestyle and medications such as ACE inhibitors, ARBs, calcium channel blockers, and vasodilators, depending on the underlying cause. In acute settings, clinicians may use vasopressors or vasodilators to adjust tone as needed.