Hypertension 2 Flashcards
How do you assess end organ damage?
- ECG
- Echocardiogram
- Proteinuria
- Renal ultrasound
- Renal function
What treatable causes do you screen for?
- Obesity
- Renal artery stenosis/Fibromuscular dysplasia
- Endocrine causes
- Coarctation of aorta
- Drug induced
- Sleep apnoea
What is stage 1 hypertension treatment for people <80 years?
Offer antihypertensive drug treatment to people <80 years with one or more of the following:
- Target end organ damage
- Established cardiovascular disease
- Renal disease
- Diabetes
- 10 year CV risk 10% or greater
What is the stage 1 hypertension treatment in <40 patients?
Seek specialist evaluation for secondary causes of hypertension and a more detailed assessment of potiential end organ damage
What is the stage 1 hypertension treatment for age 55-80?
Offer the same antihypertensive drug treatment as age 55-80 (taking into account any co-morbidieties) but BP target of 145/85
What is stage 2 hypertension treatment?
Offer antihypertensive drug treatment to people of any age with stage 2 hypertension
What is step 1 of choosing antihypertensive drug treatment in patients aged over 55 or Black people?
Start a calcium channel blocker or a thiazide like diuretic
What is step 1 of choosing antihypertensive drug treatment in patients aged under 55?
- Offer ACE inhibitor or ARB
- Not african or caribbean - less effective and higher risk of angioedema
- Women of child bearing age - teratogenic in early stages and fetal toxic in later stages.
What is the step 2 of choosing antihypertensive drug treatment?
Add thiazide type diuretic to step 1 e.g indapamide
What is step 3 of choosing antihypertensive drug treatment?
Add CCB, ACEi and diuretic together
What is step 4 of choosing antihypertensive drug treatment?
Resistant hypertension
Unable to achieve target BP despite 3 or more agents
- Consider compliance issues
- Consider higher dose thiazide like diuretic therapy (if k +>4.5)
- Consider further diuretic therapy: low dose spironolactone
Antihypertensive drugs?
Angiotensin converting enzyme inhibitors : Rampril, perindropril
Competitively inhibit the action of ACE
ACE converts angiotensin I to active angiotensin II which is a potent vasoconstrictor
Who should ACEi not be used on?
- Renal artery stenosis: may precipitate renal failure or renal infarction
- Impaired renal function
- Hyperkalaemia
- Fertile female
What are the drug-drug interactions?
- NSAIDs: precipitate acute renal failure
- Potassium supplements/potassium sparing diuretics - Hyperkalaemia
What are examples of angiotensin II receptor blockers?
Losartan, valsartan and candesartan
- ARBs competitively inhibit the action of angiotensin II at the angiotensin AT1 receptor
What are the advantages of ACEi?
Fewer side effects
Calcium channel blockers (CCB)
Vasodilators
- Eg amlodipine, felodipine
- Reduce peripheral vascular resistance
- Age >55
- Women of child bearing age (nifedapine)
Rate limiting Ca2+ blockers
- Eg Verapamil
- Reduce HR and produce some vasodilation
They both block the L type calcium channel in the myocytes of the vasculature and heart
What are the adverse drug reactions of calcium channel blockers?
- Flushing
- Headache
- Ankle oedema
- Indigestion/reflux
Rate limiting agents also cause
- Bradycardia
- Constipation
Why should calcium channel blockers not be used?
- Acute Mi
- Heart failure
- Bradycardia (rate limiting CCBs)
Thiazide type diuretics
Eg Indapamide
- Commonly first line therapy in mild-mod hypertension in people of african/caribbean origin
- Can be used in combination with any other anti-hypertensive
- Proven benefit in reducing risk of stroke & myocardial infarction
- Low doses that dont cause significant diuresis
What is the mechanism of action of thiazide type diuretics?
- Enhance urinary excretion of sodium
- Resistance vessel dilation - reduce peripheral vascular resistance
- Full antihypertensive effect may take weeks
- Adverse drug reactions are not common but include gout and ED
What are the less commonly used agents?
Alpha adrenoceptor antagonist
Centrally acting agents
Vasodilators: Hydralazine and minoxidil
What are centrally acting agents?
Methyldopa and moxonidine
- Methyldopa is used in hypertension in pregnancy
- Adverse effects : Sedation, drowsiness, dry mouth and orthostatic hypotension
What are alpha adrenoceptor antagonist?
Doxazosin
- Opposes vascular smooth muscle contraction in the arteries
- Adverse effects: 1st dose hypotension, dizziness, dry mouth headache
What is the common treatment regimes for age >55 or african/caribbean orIgin?
- Start CCB
- Add thiazide diuretic
- Add ACEi/ARB
- Add beta blocker or alpha blocker (bisoprolol or doxazosin)
- Add less commonly used agent
What are the common treatment regime for age <55?
- Start ACEi
- Add thiazide diuretic
- Add CCB
- Add beta blocker
- Add less commonly used agent
