In Pulmonary hypertension does pulmonary artery constriction occur or dilation?
Reading File
Finding Sources
Searching PubMed
"pulmonary hypertension" AND vasoconstriction
Searching the Web
pulmonary hypertension pathophysiology pulmonary arterial vasoconstriction dilation authoritative
In pulmonary hypertension, the small pulmonary arteries and arterioles primarily constrict. This raises pulmonary vascular resistance, so the right ventricle must pump against higher pressure.
Over time, there is also vascular remodeling: thickening of the vessel wall, smooth-muscle proliferation, fibrosis, and sometimes in-situ thrombosis, which further narrows the lumen.
A distinction:
- Vasoconstriction/narrowing: the key mechanism causing increased resistance, especially with hypoxia.
- Dilation of the main pulmonary artery: can occur later because the high pressure stretches the large pulmonary artery. This does not mean the small resistance vessels are dilated.
So, both can be seen anatomically, but the disease mechanism is mainly constriction and narrowing of small pulmonary vessels.
This is a shared conversation. Sign in to Orris to start your own chat.