Hypertension Flashcards
Blood pressure
Force per unit area exerted by blood on arterial walls
When does blood pressure peak
Mid systole - systolic bp
When is blood pressure lowest
End of diastole - diastolic bp
What blood pressure value shows hypertension
140/90
What physiological determinants effect blood pressure
Cardiac output
Systemic vascular resistance
What impacts cardiac output
Heart rate
Diastolic blood volume
Heart contractility
What impacts systemic vascular resistance
Arterial blood vessel diameter
Function of vessel smooth muscle tone
Endothelial wall stiffness
What conditions can hypertension lead too
Hypertensive heart disease
Left ventricular hypertrophy
Dilated cardiomyopathy
Myocardial infarction
Hypertensive kidney disease
Hypertensive retinopathy
Haemorrhagic stroke
Ischaemic stroke
How does hypertension affect afterload
increases - HTN increases systemic vascular resistance
How is the heart remodelled to overcome increased afterload in hypertension
Left ventricular hypertrophy to produce higher end systolic pressure
What is left ventricular hypertrophy
Left ventricular wall thickens
What can left ventricular hypertrophy lead to
Diastolic myocardial dysfunction
Systolic myocardial dysfunction
Dilated cardiomyopathy
Congestive heart failure
What can occur is heart muscle is not well perfused
Myocardial ischaemia
Myocardial infarction
Arrhythmia
How are blood pressure and kidney damage linked
Kidneys have role in bp regulation
Which pre-existing conditions enhance susceptibility to accelerated renal damage from hypertension
Renal disease
Diabetes mellitus
What part of the kidney is damaged by hypertension
Nephron glomeruli
How do nephrons compensate for glomurular damage from hypertension
Vasodilation of afferent arterioles to incr renal blood flow and glomerular filtration
What does vasodilation of afferent arterioles lead to
Incr glomerular bloodflow and and filtration
Glomerular hypertension
Glomerular hyperfiltration
Progressive glomerular sclerosis
How does hypertension increase CVA risk
Large and medium vessel Atherosclerosis
Small vessel lipohyalinosis
Cardio-emboli stroke
How does hypertension cause atherosclerosis
Stress on arteries causes vessel damage where fats can build up
How does hypertension cause small vessel lipohyalinosis
Vessel walls damaged by lipid accumulation and decreased luminal diameter, increasing risk of rupture and bleeding
How does hypertension cause cardioembolic stroke
Increased afterload and atrial dilation lead to atrial fibrillation
What damage can hypertension cause in retinal blood vessels
Arteriolar narrowing and abnormalities where arterioles and venues cross
Haemorrhages from retinal capillaries
What are silver/copper wire arterioles in the eyes
Arterioles swell due to arteriolar narrowing and the centre shines due to reflected light
What are cotton wool spots in eyes
Haemorrhages from retinal capillaries
How many stages of hypertension are there
3
What bp values are stage 1 hypertension
Clinic - Systolic 140-159 and/or Diastolic 90-99
Ambulatory - systolic 135-149 and/or diastolic 85-94
What bp values are stage 2 hypertension
Clinic - systolic 161-180 and/or diastolic 100-119
Ambulatory - systolic 150 and/or diastolic 95
What bp values are stage 3 hypertension
Clinic systolic 180 and/or diastolic 120
What bp values show prehypertension
Systolic 120-139
Diastolic 85-89
What is isolated systolic hypertension
High systolic pressure, normal diastolic pressure
What is the most common form of hypertension in people over 65
Isolated systolic hypertension
What underlying conditions can cause isolated systolic hypertension
Artery stiffness
Hyperthyroidism
Diabetes
Heart valve problems
Obesity
Which arm should blood pressure be measured in
Both
When may an automated bp device not get an accurate measurement
Pulse irregularity
Measures to get an accurate bp reading
Patient seated for 5+ mins
Correct cuff size
Check pulse is regular
Check more than once
Check outside clinic
Manual bp measuring method
Inflate 20-30mmHg above loss of radial pulse
Deflate 2mmHg per sec
1st sound = systolic bp
2nd sound = diastolic bp
Primary hypertension
No obvious direct underlying pathological cause
Secondary hypertension
Clear underlying cause
Secondary hypertension causes
Renal disease
Renovascular disease
Endocrine disease
Coarctation of the aorta
Latrogenic
Which enzymes are involved in the RAAS system
Renin
Angiotensin converting enzyme
What physiological effect activates the RAAS
Decreased renal perfusion pressure
What are the effects of the RAAS system
System pic vasoconstriction
Increased renal sodium reabsorption
Natriuretic peptides
Peptide hormones synthesised by the heart
Where is ANP synthesised
Atria
Where is BNP synthesised
Cardiac ventricles
What is released in response to atrial and ventricular dilation
Natriuretic peptides
What do ANP and BNP cause
Vasodilation
Decreased renin
Increased glomerular filtration rate
What hormones are released when bp increases
ANP
BNP
What hormones are released in response to decreased BP
Local + systemic noradrenaline
Systemic adrenaline
How do local noradrenaline, systemic noradrenaline, and systemic adrenaline increase bp
Incr heart rate
Incr myocardial contractility
Systemic vasoconstriction
What are genetic impacts on hypertension risk
Sodium channels
Angiotensinogen
Aldosterone
ANP + BNP
Non modifiable risks for hypertension
Age
Sex
Family history
Black ancestry
Modifiable risks for hypertension
Weight
Activity
Salt
Stress
Alcohol
Smoking
What is the DASH diet
Low fat, low meat, 8-10 fruit/veg, whole grains, low sodium
What are the 3 parts of metabolic syndrome
Central obesity
Hypertension
Insulin resistance
How does diabetes contribute to hypertension
Sclerosis
Increases SVR via -
atheroma formation
Hyperglycaemia
Disordered lipid profile
Vascular endothelium damage
Decr NO production
Lifestyle modifications for hypertension patients
Potassium rich diet
DASH diet
Weight maintenance/loss
Exercise
Limit alcohol
Smoking cessation
When should a hypertensive patient not have a potassium rich diet
Chronic kidney disease
On medication that reduces potassium excretion
When should stage 1 hypertension be treated with drugs in under 80s
If patient has 1 or more of -
Target organ damage
Established CV disease
Renal disease
Diabetes
Estimated 10 yr risk of CV disease over 10%
Clinical judgement - frailty or multimorbidity
What additional measures should be used for patients under 40 with hypertension
Specialist evaluation of secondary causes
Detailed assessment of long term treatment benefits and risks
What are the main classes of hypertensive drugs
ACE inhibitors
Angiotensin II receptor antagonists
Calcium channel blockers
Diuretics
Beta blockers
What drug class in enalapril
ACE inhibitor
What drug class in losartan
Angiotensin II receptor antagonist
What drug class is amlodipine
Calcium channel blocker
What drug class is indapamide
Thiazide like diuretic
What drug class is metoprolol
Beta blocker
Why should ACE inhibitors and angiotensin II receptor antagonists not be used in pregnant or breastfeeding women
Teratogenic
How many steps to hypertension treatment
4
At what stage should hypertensive drug treatment be used
Stage 2
Stage 1 w comorbidities
When should an ACE inhibitor or ARB be used in step 1 of HTN treatment
Type II diabetes
Aged under 55 and not black African/ Afro Caribbean origin
When should a calcium channel blocker be used to treat stage 1 hypertension
Over 55 and no type 2 diabetes
Black African/ Afro Caribbean origin and no type 2 diabetes
Can an ace inhibitor and ARB be combined for hypertension treatment
No
What is given in step 2 treatment of a hypertension patient on an ACE inhibitor or ARB
CCB or thiazide like diuretic
What is given in step 2 treatment of a hypertension patient on a CCB
ACE inhibitor or ARB or thiazide like diuretic
What is given in step 3 hypertensive treatment
ACE inhibitor or ARB
CCB
Thiazide like diuretic
What is hypertension regarded as if not controlled by step 3 treatment
Resistant hypertension
How is resistant hypertension treated (step 4 treatment)
Fourth hypertensive drug or specialist advice
How should resistant hypertension be confirmed before starting step 4 treatment
Confirm bp with ambulatory or home measurements
What should be done if bp is not decreasing with treatment
Discuss medication adherence w patient
Discuss how meds are being taken w patient
Consider secondary causes
What is evidence of end organ damage
Papilloedema
Retinal haemorrhage
Mental status changes
Chest pain
Dyspnoea
Acute heart failure
Acute kidney injury
What is a hypertensive emergency
BP 180/120 +
Evidence of end organ damage
How are hypertensive emergencies treated
Immediate specialist referral and/or hospital admission
Why should BP 180-120+ with no evidence of end organ damage not be treated until repeat measurement taken
No evidence for benefit in rapid reduction
Aggressive therapy may cause cardiac, renal, or cerebral hypoperfusion
