Hypertension Flashcards
How is someone’s BP measured ?
Systolic Pressure/ Diastolic pressure
What does systolic pressure refer to?
Peak pressure due to ventricular contraction
What does diastolic pressure refer to?
Pressure during ventricular relaxation
Ideally, what do we want BP to be below?
120/80mmHg
What is BP measured in?
mmHg
According to the NHS, what is the normal range of BP?
90/60mmHg - 140/90mmHg
When is hypertension diagnosed ?
systolic BP >140mmHg OR the diastolic BP is >90mmHg on TWO successive occasions
When can malignant HTN be classified?
Systolic > 200mmHg OR diastolic >140mmHg
What px is systolic pressure more commonly elevated?
Older px
What px is diastolic pressure more commonly elevated?
Younger px (<50yrs)
What is HTN a RF for ? (There are 7)
- Stroke
- Myocardial infarction (heart attack)
- Heart failure
- Chronic kidney disease
- Peripheral vascular disease
- Cognitive death
- Premature death
What happens if BP is left untreated?
BP will continue to rise and become resistant to treatment
What are two categories HTN can be classified into?
Primary or secondary (due to another disease
*primary account for 90% of cases
What are four non-modifiable RF for HTN?
- age
- race (higher in Afro-Caribbean)
- fh
- pregnancy
What are some modifiable RF for primary HTN?
- regular exercise
- healthy diet
- relaxation
- alcohol reduction
- reduce sodium intake
- increase potassium intake
Why is it important we are aware about HTN?
Retina is the only place where we can examine arterioles non-invasively- they look v similar to cerebral and coronary ones so can show they are at risk of a heart attack or stroke
Will elevated BP affect inner and outer retinal circulation similarly?
No- effects them differently
What kind of junctions are in the inner retinal vasculature?
Tight junctions- they form the blood retinal barrier
What is autoregulation?
When the diameter of blood vessels change in repose to change in BP (high BP = vasoconstriction)
Do inner retinal vasculature show auto regulation?
Yes
Do choroidal arterioles exhibit auto regulation ?
No
Why does hypertensive retinopathy happen?
- Constant high BP
- constant constriction of retinal arterioles
- narrowed BVs to regulate blood flow
- leads to diffuse and focal arteriolar narrowing
- increased tortuosity
What does long term hypertension cause?
Arteriolosclerosis
What is aterteriolosclerosi?
Thickening + stiffening of arteriolar wall
How many stages are there of HR?
4
What is stage 1?
Mild to moderate narrowing or sclerosis of the arterioles
What is stage 2?
- Mod to marked narrowing of arterioles (can be generalised or local)
- Exaggeration of light reflex
- Arteriovenous crossing changes
What is stage 3?
- arterioles Narrowing + focal constriction
- Retinal oedema
- CWS
- Retinal haemorrhages
- Hard exudates
What is stage 4?
All of stage 3 + OD swelling
Which two stages are chronic ?
1 & 2, they will be asymptomatic
Which stages would a px be symptomatic + acute (short term high spike in BP)?
3 & 4
What is the name of the classification system to grade HR?
Keith-Wagener Barker Classification of hypertensive retinopathy
What will the BV look like in stage 1 and stage 2?
Straighter and narrower
In an older px with hypertensive retinopathy, why may you not see much of a difference in the a/v ratio?
Due to arteriosclerosis (thickening of cell walls stops them constricting)
What can arteriosclerosis lead to ?
Change in light reflex from the vessels
Why can we see a change in light reflex?
Because vessel walls becomes opaque —> broader, duller, diffuse reflex
What is the way we describe the light reflex in HR?
Copper-wire appearance
When would you see a ‘silver wire’ appearance?
When the sclerosis advances
How does the arteriovenous crossing alter?
Nipping occurs
What is nipping?
Venule is compressed by sclerosed arteriole
If blood flow of the vein is reduced due to nipping, what may you see?
Vein after the crossing becomes more tortuous, larger and darker
If there is severe changes to A/V crossing, what may happen?
BRVO
What acute rise in BP mean?
Over short period of time the BP has spiked
What occurs with the blood-retinal barrier in stage 3&3 of HR?
Disruption of the blood retinal barrier
What happens when the blood-retinal barrier is disrupted?
Increased vascular permeability
With severe HTN, can the arteries autoregulate?
NO, they lose their ability to do so
As the arteries cannot autoregulate, what happens? And how does this affect capillaries?
Blood flow cannot be moderated as it should + leads to damaged arterioles and capillaries
What signs may you see with a px who’s arteries cannot auto regulate? (There are two)
Microaneururysms and CWS
What is CWS a sign of ?
Retinal Ischaemia (axoplasmic flow is disrupted by this ischaemia)
What does increased vessel permeability lead to?
Leakage
What are four signs you may see with someone who has increased vessel permeability?
- Flame haemorrhages
- Retinal oedema
- Hard exudates
- Macula star
What are four signs you may see with someone who has increased vessel permeability?
- Flame haemorrhages
- Retinal oedema
- Hard exudates
- Macula star
What are hard exudates a leakage of ?
Lipoproteins
Why does a macula star happen?
The hard exudates follow the path of the fibres of Henle
What is swelling of the optic disc a sign of?
Malignant HTN
Describe this picture.
Stage 4 HTN, poorly defined margins, papilloedema, tortuous vessel, macula star
What stage is this?
4
What is fibrinoid necrosis?
the inside lining of your blood vessels becomes damaged.
What happens as a result of unregulated high BP?
Fibrinoid necrosis of end of arterioles
What % of px with primary HTN will develop malignant HTN?
1%
Why is malignant HTN rapidly fatal?
Can lead to heart failure, stroke, myocardial infarction or renal failure - DEATH
What are 9 symptoms a px with malignant HTN may have?
- HAs
- Diplopia
- Scotoma
- Dimness in Vision
- Photopsia (flashes)
- Chest pain
- Nausea/vomiting
- Shortness of breath,
- Weakness
Which stages of HR may we see hypertensive choroidopathy?
3&4
What is indicative of hypertensive choroidopathy ?
Yellow spots in the RPE showing the ischaemic parts of the choroid
*yellow spots are ischaemic infarcts
Why does hypertensive choroidopathy happen?
Fibrinoid necrosis of choroidal vessels which leads to choroidal ischaemia
What six signs can hypertensive choroidopathy lead to?
- Diffuse pigment granularity in the RPE
- Pigment clumping surrounded by atrophic areas
- Hyperpigmented flecks
- rpe detachment
- Serous RD
- Cystoid macula oedema
What do the pigment clumping surrounded by atrophic areas replace?
The yellow spots
How are the hyperpigmented flecks arranged? And what is the name of these flecks ?
In a linear fashion + Siegrist streaks
What do px with hypertension and DM have a higher risk of ?
Cardiovascular events
Can a px have HR AND DR in the Same eye?
YESSSSSSS
Out of HR stage 3 and DR R3 which shows a ‘drier’ retina ?
HR stage 3
Out of HR and DR which disease is more likely to have flame haemorrhages?
HR, DR More likely to have dot and boor
What anterior eye condition is associated with HTN ?
Sub-conjucntival haemorrhage
What stage is optic nerve head swelling a feature of ?
Stage 4
After treatment of stage 4 HTN, what might the optic nerve head still look like?
Nerve pallor, optic nerve dysfunction
What can acute obstructions of the supplying the optic nerve head lead to?
NA-AION (Anisha’s FAV)
What signs and symptoms may someone with NA-AION have?
- painless sudden loss of vision
- reduced va
- dyschromatopsia (reduced CV)
- RAPD
- Swollen optic disc
- VF defect
What is the main treatment of hypertensive retinopathy?
Manage the systemic HTN
At 2 months, what is the mortality rate of px with malignant HTN?
50%
What is the management for stage 1 & 2 HR?
Refer to GP for management of systemic HTN
What is the management of stage 3 HR?
Refer to GP for management of systemic HTN
AND
Refer for ophthalmological assessment
What is the management for stage 4 HR?
Medical emergency - same day referral
Once stage 3 is treated, what will remain?
Stage 1 and 2 appearance so thinning of artery walls ect
According to Keith, Wagner and Barker what are the 3-year survival rates for a px with stage I retinopathy?
70%
According to Keith, Wagner and Barker what are the 3-year survival rates for a px with untreated HTN and with stage I retinopathy?
70%
According to Keith, Wagner and Barker what are the 3-year survival rates for a px with untreated HTN and with stage II retinopathy?
62%
According to Keith, Wagner and Barker what are the 3-year survival rates for a px with untreated HTN and with stage III retinopathy?
22%
According to Keith, Wagner and Barker what are the 3-year survival rates for a px with untreated HTN and stage IV retinopathy?
6%