Hypertension Flashcards
CO X TPR =
MAP
SV x HR =
CO
What 2 systems regulate blood pressure
Sympathetic and Renin-angiotensin-aldosterone system
What type of adrenoceptors are on heart
B1
What type of adrenoceptors are on the smooth muscle
A1
What vascular changes can occur as a result of hypertension?
Remodelling, thickening, hypertrophy
What can local salt sensitivity cause?
Vascular remodelling
In hypertension, there is an increase in which vasoactive substances?
ET-1
NAd
Ang2
Hypertension can cause end organ damage such as…
Renal, peripheral vascular, aneurysm, vascular dementia, retinal disease
What figure does NICE recommend as the boundary of hypertension?
140/90mmHg
What blood pressure reading indicates emergency treatment is required?
> 180/120 + clinical signs
How would you treat prehypertension?
Promote regular exercise Modify diet Reduce stress Increase relaxation Limit alcohol Limit caffeine Smoking cessation Reduce dietary sodium
What are CCB’s?
Calcium channel blockers
What are ARB’s?
Angiotensin receptor blockers
What are ACEi?
ACE inhibitors
Thiazides and Thiazide like are subsets of which drug class?
Diuretics
Where in the body is ACE made?
Surface of pulmonary and renal endothelium
Angiotensin 2 is a?
Vasoconstrictor
Angiotensin 2 acts on AT1 receptors to elicit what responses?
Vasoconstriction
Stimulation of aldosterone
Cardiac and vascular muscle cell growth
Vasopressin
Where in the body is vasopressin (ADH) produced?
Posterior pituitary
ACEi’s cause vasodilation, how does this help treat hypertension?
Decrease in peripheral vascular resistance which decreases afterload
How does a reduction in aldosterone release help treat hypertension?
Increase in water and Na+ excretion
Name 2 ACEi
Lisinopril
Ramipril
Lisinopril and Ramipril are examples of what type of drug?
ACEi
ACEi’s do what to bradykinin?
Potential it
What are the side effects of ACE inhibitors?
Hypotension
Dry cough due to bradykinin association
Hyperkalaemia - low aldosterone = increase K+
Renal failure
Angioedema due to ACEi is more common in which population?
Black population
What warnings and contraindications are associated with ACEi’s?
Renal artery stenosis
AKD
Pregnancy
Breast feeding
What important interactions should you be aware of when prescribing ACEi’s?
Drugs that increase K+
NSAIDs
Other antihypertensives
Candesartan and Losartan are examples of what class of antihypertensives?
ARBs
Why are ARBs not associated with a dry cough and angioedema?
No effect on bradykinin
ARBs are less affective in what type of hypertensive
Low renin hypertensive
ARBs that directly target AT1 receptors are more effective at inhibiting what effect
Angiotensin2 mediated vasoconstriction via chymase production
What are the warnings and contraindications associated with ARBs
Renal artery stenosis
AKD
Pregnancy
Breastfeeding
What interactions are important to consider when prescribing ARBs?
Drugs that increase K+
NSAIDs
Other antihypertensives
What 2 types of drugs target calcium movement?
LTCC - L-type calcium channels
CCB - calcium channel blockers
LTCC’s allow the flux of calcium ions in which direction?
Inwards
LTCCs are an example of what type of ion channel?
Voltage operated calcium channel
What is the target of CCBs?
They target calcium initiated smooth muscle contraction
What drug class does Amlodipine belong to?
Dihydropyridine
The vasodilation caused by dihydropyridines causes what side effects?
Ankle swelling, flushing and headache
What are the warnings and contraindications associated with dihydropyridines?
Unstable angina, severe aortic stenosis
Why is Amlodipine + Simvastatin not adviced?
Increased effect of the statin
Verapamil belongs to which drug class?
Phenylalkylamines A class 4 anti-arrhythmic agent
When might the phenylalkylamine Verapamil be contraindicated or warned against?
If the patient has poor LV function or AV nodal conduction delay
Diltiazem belongs to which drug class?
Benzothiazapines
What type of drug is Bendroflumethiazide?
A thiazide diuretic
How do thiazide diuretics such as bendroflumethiazide elicit their action?
Inhibit sodium resorption at the distal convoluted tubules
Indapamide belongs to which drug class
A thiazide-like diuretic
What are the warnings and contraindications of Bendroflumethiazide?
Hypokalaemia
Hyponatraemia
Gout
What is the two pronged approach to treating primary hypertension?
Decrease blood pressure and dilation of the efferent glomerular arteriole to reduce intraglomerular pressure which is good for type 2 diabetes
What is Spironolactone?
Aldosterone receptor antagonist
When is Spironolactone warned against/contraindicated?
In hyperkalaemia and Addisons
What is Addison’s disease?
Adrenal insufficiency - so too little cortisol and aldosterone
What interactions should be considered when prescribing Spironolactone?
Drugs that increase K+ including ACEi and ARBs
How do beta-blockers reduce cardiac output?
Decrease sympathetic tone by blocking NAd and reducing myocardial contraction
Renin secretion is reduced when beta blockers act on which adrenoceptors?
B1
When are beta blockers warned against/contraindicated?
Asthma haemodynamic instability, hepatic failure
Why is it a problem that beta blockers can mask tachycardia?
Tachycardia is a sign of insulin induced hypoglycaemia
What drugs have interactions with beta blockers?
Non-dihydropyridine CCB: verapamil and diltiazem - asystole
Name 2 beta blockers
Labetalol
Bisoprolol
Metoprolol
Give an example of an Alpha-1 adrenoceptor?
Doxazosin
What are the possible side effects of the a-adrenoceptor Doxazosin?
Postural hypotension
Dizziness
Headache
Fatigue
