Hypertension Flashcards
Stages of HTN in terms of clinical BP
Stage 1 - > 140/90
Stage 2 - > 160/100
Severe - >180/110
Stages of HTN in terms of ABPM daily average
Stage 1 - >135/85
Stage 2 - 150/95
What % of HTN has an identifiable cause?
5 - 10%
What does sustained HTN produce?
End organ damage to blood vessels, heart and kidney
Causes of secondary HTN
Renal disease Drug induced Pregnancy Endocrine causes Vascular Sleep apnoea
What renal diseases can cause secondary HTN?
Chronic pyelonephritis
Fibromuscular dysplasia
Renal artery stenosis
Polycystic kidneys
What drugs can cause HTN?
NSAIDs
Oral contraceptives
Corticosteriods
What condition in pregnancy is especially associated with HTN?
Pre eclampsia
What endocrine conditions can cause secondary HTN?
Conns syndrome Cushings disease Phaechromocytoma Hypo and hyperthyroidism Acromegaly
What vascular condition can especially cause HTN?
Coarctation of the aorta
What non modifiable factors does BP tend to increase with?
Age
Genetics
FH
Race (afrocarribean)
What in the environment can increase your BP?
Stress
What can raise BP?
Co morbidities
Age
Weight (sodium intake and diet)
Alcohol intake
Relationship between birth weight and HTN
Lower the birth weight, higher the likelihood of developing HTN and heart disease
Definition of primary HTN
HTN where there is no identifiable cause
Definition of secondary HTN
HTN where there is an identifiable cause
What % of cases are primary HTN?
95%
What % of cases are secondary HTN?
5 - 10%
Risk factors for HTN
Smoking DM Renal disease Male Hyperlipidaemia Previous MI or stroke LVH Sedentary lifestyle
What are the prime contributors to BP?
Cardiac output
- SV
- HR
Peripheral vascular resistance
What does the sympathetic nervous system activation cause?
Vasoconstriction
Reflex tachycardia
Increased cardiac output
= INCREASED BP
What is pivitol in long term blood pressure control?
RAAS
What does RAAS stand for?
Renin angiotensin aldosterone system
The RAAS is responsible for what?
Maintenance of sodium balance
Control of blood volume
Control of BP
What is the RAAS stimulated by?
Fall in BP
Fall in circulating volume
Sodium depletion
What happens when RAAS is stimulated?
- Renin release from juxtaglomerular apparatus
- Renin converts angiotensin to angiotensin I
- Angiotensin I is converted to angiotensin II by angiotensin converting enzyme (ACE)
- Angiotensin II constricts, and stimulates aldosterone release from adrenal glands
What does angiotensin II do?
Potent
- vasoconstrictor
- anti natriuretic peptide
- stimulator of aldosterone release from the adrenal glands
- hypertrophic agent which stimulates myocyte and smooth muscle hypertrophy in the arterioles
What does aldosterone do?
Potent
- anti-natriuretic peptide
- antidiuretic peptide
What are poor prognostic indicators in patients with HTN?
Myocyte and smooth muscle hypertrophy
Examples of end organ damage that HTN can cause
Retinopathy Peripheral vascular disease Coronary heart disease Heart disease Renal failure Proteinuria Stroke Cognitive decline LVH MI
HTN treatment goal elderly vs young people
Elderly target BP is higher than in young people
How may HTN be identified?
ABPM ambulatory blood pressure monitoring
HBPM home blood pressure monitoring
How do we assess renal function?
eGFR
How do we assess cardiac function?
ECG
ECHO
What treatable causes of HTN must be screened for?
Renal artery stenosis / FMD
Cushings disease
Conns syndrome
Sleep apnoea
What should be an ideal target BP to be obtained on treatment?
< 135/80-85mmHg
When should treatment for BP be started?
Overall CVD risk of 20% / 10 years
What should be used to treat young for HTN?
ACE inhibitor
ARB
Do the young have high or low renin?
High
What should be used to treat the elderly for HTN?
CCBS
Thiazide type diuretic
Do the elderly have high or low renin?
Low
Who should ACE inhibitors / ARBs not be used in in the young group?
Young women
Who should the treatment for stage 1 HTN be given to?
If < 80 y/o with ABPM > 135/80 with 1 or more of
- target organ damage
- established CVD
- Renal disease
- DM
- 10 yr CV risk equivalent to 20% or greater
If < 40 y.o get specialist advise
What BP is stage 1 HTN?
ABPM > 135 / 85
What BP is stage 2 HTN?
ABPM > 150 / 95
Who should the treatment for stage 2 HTN be given to?
Any people of any age with stage 2 HTN - the risk does not matter here
Treatment for HTN for > 55 y/o or black people of any age
CCB
TTD if oedema / intolerance / HF
Treatment for HTN for < 55 y/o
ACEI or ARB
Why do afro-carribeans not get treated with ACEIs/ARBs?
Susceptible to swelling of the epiglottis/face
Step 2 treatment for HTN
Add TTD to CCB or ACEI/ARB
Step 3 treatment for HTN
Add the other drug that you haven’t used - so add CCB, ACEI and diuretic together
Treatment for resistant HTN
Low dose spironolactone (25mg once daily) if blood K+ is <4.5mmol/l
TTD if blood K+ is over 4.5mmol/l
Why should treatment with spironolactone be cautioned with in reduced eGFR?
They have an increased risk of hyperkalaemia
Examples of ACEIs
Ramipril
Perindopril
What does ACEIs stand for?
Angiotensin converting enzyme inhibitors
What do ACEIs do?
Completely inhibit actions of angiotensin converting enzyme (ACE)
Contraindications to ACEIs
Renal artery stenosis
Renal failure
Hyperkalaemia
Adverse drug reactions of ACEIs
Cough 1st dose HTN Taste disturbance Renal impairment Hyperkalaemia Angioneurotic oedema
Drug drug interactions of ACEIs
NSAIDs
Potassium supplements
Potassium sparing diuretics
What would ACEIs and NSAIDs together result in?
Precipitation of acute renal failure
What would potassium supplements and potassium sparing diuretics with ACEIs result in?
Hyperkalaemia
Examples of ARBs
Losartan
Valsartan
Candesartan
Irbesartan
What do ARBs stand for?
Angiotensin II antagonists
What do ARBs do?
Competitively block the actions of angiotensin II at the angiotensin AT1 receptor
Why do ARBs have an advantage over ACEIs?
They do not cause a cough
What is the most effective ARB?
Losartan
Types of CCBs
Vasodilators
Rate limiting
Examples of vasodilator CCBs
Amlodipine
Felodipine
Examples of rate limiting CCBs
Verapamil
Diltiazem
How do CCBs work?
Block the L type calcium channels
Selectivity between vascular and cardiac L type channels
Relaxing small and large arteries and reducing peripheral resistance
Reducing CO
Who are vasodilator CCBs the antihypertensive of choice in?
> 55 y/o
Women of child bearing age
Contraindications of CCBs
Acute MI
Heart failure
Bradycardia (rate limiting CCBs)
S/Es of CCBs
Flushing
Headache
Ankle oedema
Indigestion and reflux oesophagitis
What do rate limiting CCBs also cause?
Bradycardia
Constipation
Examples of TTDs
Indapamide
Clortalidone
Who is TTDs commonly the 1st line treatment in?
Mild - moderate HTN in afro-carribeans
How do TTDs work?
Block reabsorption of sodium and enhance urinary sodium loss
The full effects of TTDs as anti-HTNs may take how long?
Weeks
S/Es of TTD
(Not common)
Gout
Impotence
Hypokalaemia
Centrally acting agents like methyldopa can cause what?
Depression
Examples of vasodilators
Hydralazine
Minoxidil
S/Es of vasodilators
Dry mouth
Bad dreams
Effects of NSAIDs
Salt and water retention - causing increased BP
Shuts off prostaglandin production
What causes a displaced apex?
LVH
What does LVH stand for?
Left ventricular hypertrophy
What else can be looked for in LVH?
4th heart sound - diastolic knock
What murmur causes a collapsing pulse?
AR
How should BP be checked?
Lying
Standing
Both sides
Man with HTN aged 48 y/o, what investigations should be done?
U and Es (esp Na+ and K+) Lipids Urine dipstick LFTs Thyroid Glucose ECG ECHO Kidneys/adrenal glands via USS
Potassium level in conns syndrome
Decreases
Potassium level in phaeochromocytoma
Increases
What does acute alcohol intake do to BP?
Decreases BP
What does chronic alcohol do to BP?
Increases BP
If BP >140/90, what should be offered to confirm the diagnosis?
ABPM
LVH on ECG
S wave on V2 and V5 added together, if > 30mm = LVH
S/Es of alpha blockers
Postural hypotension
HF
Contraindication to alpha blockers
Urinary incontinence
When should there be a caution in using BBs?
DM
S/Es of ARBs
Hyperkalaemia
S/Es of spironolactone
Hyperkalaemia
What treatment should be added onto poorly controlled HTN already on an ACEI, CCB and a standard dose TTD with a K > 4.5mmol/l?
Alpha or beta blocker
What do ACEIS cause (in terms of electrolytes) as a S/E?
Hyperkalaemia
What do diuretics’ cause (in terms of electrolytes) as a S/E?
Hypokalaemia
BP target for a clinic reading and < 80 y/os
< 140 / 90
Max dose of amlodipine
10mg
Max dose of ramipril
5mg
If a patient cannot tolerate and ACEI due to the S/Es, what should be done to the medication?
Stop the ACEI
Change to an ARB
Give an example of an ARB
Candesartan
1st line treatment for a newly diagnosed patient with HTN who has T2DM
ACEI or ARB - REGARDLESS of age
Pharmacological options for treatment of orthostatic hypotension
Fludrocortisone
Midodrine
Treatment of orthostatic hypotension
- Lifestyle measures - increased Na and H20 intake
- Discontinuation of vasoactive drugs e.g. nitrates, anti-HTNs, neuroepileptic agents, dopaminergic drugs
- If symptoms persist, consider compression garments, fludrocortisone, midodrine, counter pressure manouvres, head up tilt sleeping
Target BP for a T1DM who has HTN, but no albuminuria
< 135/85
