Pathophysiology of Hypertension Flashcards
what is the difference between systemic and pulmonary hypertension?
systemic is more common than pulmonary hypertension
how are the causes of pulmonary hypertension classified?
- idiopathic=unknown
- secondary to some known cause
what are the causes of pulmonary hypertension?
- hypoxia, altitude- low O2 in air- ling is detecting low levels of O2 across the lung so reflex vasoconstriction across all lung vessels
- endothelial dysfunction
- blockage or damage to pulmonary vessels
- drugs
what is hypertension?
state of elevated arterial blood pressure
what is primary hypertension?
idiopathic
define secondary hypertension.
- known cause
- renal disease, diabetes, crushings disease, pheochromocytoma
what are the classifications of hypertension?
stage 1- clinical BP 140/90at home 135/85
stage 2- clinical BP 160/100 at home 150/95
what are the possible causes of primary hypertension?
-increase in total peripheral resistance
-increase in sympathetic nerve activity
increased vascular reactivity
-damage to endothelium
-altered blood vessel wall morphology
how is increased vascular reactivity a possible cause of hypertension?
- increased response to a signal
- increased Na in extracellular fluid increases amount of sodium which fluxes into the cell decreasing the ability of the cell to depolarise
- inhibition of Na/K ATPase in kidney will alter blood volume by retaining more fluid
how does damage to endothelium lead to hypertension?
decreases nitric oxide production which increases the resistance of the vessels
What are the causes of secondary hypertension?
- renal disease
- diabetes
- endocrine disease
- coarcrtation of aorta
- drugs
- pregnancy
how does renal disease lead to hypertension?
if kidneys don’t function you can’t produce urine output to lower your blood volume
how does diabetes lead to hypertension?
increase in oxidative stress in vessels resulting in damage to endothelium and also hyperglycaemic affect can also damage endothelium
what are modifiable risk factors for hypertension?
diet, exercise, obesity, alcohol,stress , smoking
what are the genetic risk factors of hypertension?
abnormal inhibition of Na/K ATPase, family history, being of african or carribbean origin
