Hypertension Flashcards
(42 cards)
What are the possible causes of secondary hypertension
Renal disease renovascular disease Conn's syndrome Cushing's syndrome Hyperthyroidism Phaeochromocytoma Pregnancy Drusgs
How does renovascular disease have an effect on blood pressure
Narrowing of renal artery has an effect on renin-angiotensin
How does Conn’s disease have an effect on blood pressure
Aldosterone formed because of conn’s disease means there is an increase in sodium and water retention
How does pheochromocytoma have an effect on blood pressure
Tumour releasing noradrenaline which increases blood pressure
What are the environmental causes of changes in blood pressure
Nitrates in some water can decrease blood pressure
What is the biggest diagnostic for high blood pressure and therefore what does treatment aim to reduce to reduce high blood pressure
Systole
Treatment aims to reduce systolic bp
How does obesity lead to high blood pressure
Production of angiotensin from adipocytes
What is the main goal of treatment when treating hbp
Reduction in blood pressure with as few side effects as possible
What are specific goals of hbp treatment
- reduction in cardiovascular damage
- preservation of renal function
- LImitation or reversal of left ventricular hypertrophy
- Prevention of Ischaemic Heart Disease
- Reduciton in mortality due to stroke and myocardial infarction
Formula for blood pressure
BP= CO x TPR
TPR=total peripheral resistance
How do ACE inhibitors reduce bp
Inhibit ACE and so there is reductions in arterial and venous vasoconstriction. Also reduced aldosterone production so there is a reduction in salt and water retention
What are the side effects of ACE inhibitors
patient may develop a cough
When should ACE inhibitor not be used
In renovascular disease because ACEi lead to renal underperfusion and severe hypotension
What drug is beneficial for patients with diabetes as well as those with hbp
ACE inhibitors
Why are ACE inhibitors beneficial for patients with diabetes
ACE inhibitors are effective at the prevention of nephropathy in diabetes
What can the renin-angiotensin system be stimulated by
Sympathetic nervous system
What is a risk of ACE inhibitors and why
Hypocalaemia because there is an increase in sodium retention and increase in potassium loss
Why are rate limiting drugs (some calcium channel inhibitors) not used for heart failure
As they reduce the force of contraction of the heart which will make the heart failure worse
What drug would you use for those with heart disease and HBP
DHP
What is the action of AT1 receptor antagonists
Block the action of A2 at the AT1 receptor therefore the production of aldosterone is inhibited and there is no vasoconstriction
What drug is used instead when the ACE inhibitors give rise to a cough
AT1 receptor antagonist
What are some vasodilators
Calcium channel inhibitors i.e. diltiazem, verapamil, and dihydropyridines
What do calcium channel inhibitors do
Inhibit voltage operated Ca2+ channels on vascular smooth muscle
What do rate-limiting calcium channel inhibitors (eg verapamil) do
Have a greater effect on cardiac tissue
