Hypertension + hypertensive drugs Flashcards
why is high BP harmful?
risk factor for CHD + strokes
can lead to endothelial cell damage + internal organ damage
excessive strain on heart
-> left ventricular hypertrophy
-> congestive heart failure
cardiovascular risk factors
high BP
smoking
high salt intake
alcohol
lack of exercise
obesity
dyslipidaemias
diabetes
genetics
gender/age
stage 1 hypertension
clinic BP <140/90 mmHg
ABPM/HBPM < 135/85 mmHg
lifestyle changes
what conditions do patients have to meet to get treatment for stage 1 hypertension?
age <80
target organ damage
CV/renal disease
diabetes
stage 2 hypertension
clinic BP > 180/120 mmHg
ABPM/HBPM > 150/96 mmHg
= treatment with lifestyle changes
what does hypertensive treatment do
reduces total peripheral distance (reduces after load)
reduces SV (lowers BV and preload)
reduces HR
when is low BP detected?
carotid sinus
aortic arch
juxtaglomerular cells
macular dense cells sensing less Na+ / Cl- flowing through tubules
what happens when renin is secreted?
causes angiotensinogen to be converted to angiotensin I
angiotensin I is converted to angiotensin II by ACE
what does angiotensin II cause?
efferent arterioles to constrict more than afferent arteriole
= higher GFR
= proximal tubule to reabsorb more Na+
= more thirsty
= higher BP
= aldosterone release (= kidneys to retain Na+ and H2O)
ACE2
counter-regulator of ACE
hydrolyses angiotensin II to angiotensin (1-7)
3 types of antihypertensive drugs
ACE inhibitors (ACEI)
ATI receptor blockers (ARBs)
renin inhibitors
ACE on bradykinin
reduced
where is bradykinin produced
by kiniogen protein in CVS and lungs
effect of ACE inhibitors on bradykinin
increased = dry cough
can lead to angioedema (swelling of deeper layers of skin, caused by build-up of fluid)
how do ARBs work
block AT1 receptors which lead to reduced aldosterone/vasoconstriction