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Flashcards in Vascular disease: Hypertension Deck (55)
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1

what is arteriosclerosis

is hardening of the arteries, condition not only thickens the wall of arteries, but also causes stiffness and a loss of elasticity

2

what is atherosclerosis

is the most common type of arteriosclerosis, or hardening of the arteries, and caused by plaque building up in the vessel

over time the plaque causes thickening of the walls of the artery. Stiffness and a loss of elasticity also result.

3

a patient with arteriosclerosis (hardened arteries) may not have...

atherosclerosis (plaque), but a patient with atherosclerosis does have arteriosclerosis

4

what is blood pressure and what does it refer to

Pressure exerted by circulating blood upon the walls of blood vessels

Usually refers to systemic arterial pressure measured at a person's upper arm

5

what is blood pressure recorded as and what does each component stand for

Systolic Pressure (mmHg)/Diastolic Pressure (mmHg)

Systolic = Peak pressure due to ventricular contraction (systole)

Diastolic = Pressure during ventricular relaxation (diastole) when chambers of heart are filling with blood

6

describe the distribution of blood pressure

Blood pressure is normally distributed in the population
The avg systolic = 110mmHg with the long tail off to the higher pressure end

No definitive cut-off for normality – risk of disease increases continuously with increasing pressure

7

what is normal blood pressure range according to the NHS

90/60mmHg to 140/90mmHg

8

when is hypertension diagnosed

when the systolic blood pressure is above 140mmHg or the diastolic blood pressure is above 90mmHg on TWO successive occasions

9

when is malignant hypertension diagnosed

when the systolic blood pressure is above 200mmHg or the diastolic blood pressure is above 140mmHg

10

what is the prevalence of HTN in the population and what is the prevalence in over 60's

more than 25% of the UK population
and
more than 50% of those aged over 60yrs

11

what 2 classifications can HTN be

can be primary 90% of cases
or
secondary 10% of cases

12

what can a secondary HTN be from and what is the prevalence

to renovascular disease, ~10%

13

list the 5 conditions that are risk factors for HTN

Stroke
Heart failure, Chronic kidney disease
Peripheral vascular disease (e.g retinopathy)
Cognitive decline
Premature death

14

list all 4 non modifiable risk factors of HTN

Increasing age
Race (higher risk at younger age in afro-caribbean people)
Family history
Pregnancy

for these patients you can't do anything about, but its worth being aware of these px's so we can monitor them closely and their retinal appearance carefully

15

list 6 modifiable factors that all have a positive affect on HTN

regular exercise
healthy diet
relaxation
alcohol reduction
reduced sodium intake
increased magnesium intake

16

what can be studies non-invasively regarding HTN

the retinal arterioles by looking at the back of the eye

17

give 2 reasons why looking at the retinal arterioles via the eye a reliable method for detecting HTN

Similar anatomically to cerebral and coronary micro circulation, fundus examination may diagnose life-threatening hypertension at an early stage

Hypertension can also cause hypertensive retinopathy (a direct affect on the eyes), and optic nerve and cranial neuropathies, which threaten sight

18

what causes hypertensive retinopathy

Increased blood pressure causes constriction of retinal arterioles (autoregulatory mechanism).

Chronic vasospasm leads to diffuse and focal arteriolar narrowing and increased vascular tortuosity.

Long term hypertension causes arteriolosclerosis (thickening of arteriolar wall due to progressive hyalinisation and increase of elastic and muscular components).

Difficult to separate effects on arterioles of hyptertension from effects of arteriolosclerosis.

19

what does long term HTN cause to the arterioles in retinopathy

causes arteriolosclerosis
(thickening of arteriolar wall due to progressive hyalinisation and increase of elastic and muscular components)

20

which stages of hypertensive retinopathy are chronic and which stages are acute

chronic: stages 1 and 2 (happen in the retina in a long period of time which is asymptomatic)

acute: stages 3 and 4 (comes about when theres a rapid rise in BP which is symptomatic)

21

describe what is seen in stage 1 (chronic) of hypertensive retinopathy

Mild to moderate narrowing/sclerosis of arterioles

22

describe 4 signs seen in stage 2 (chronic) of hypertensive retinopathy

Mild to moderate narrowing/sclerosis of arterioles
Local and/or generalised narrowing of the arterioles
Exaggeration of the light reflex from the arterioles
Arteriovenous crossing changes

23

describe 4 signs seen in stage 3 (acute) of hypertensive retinopathy

Retinal arteriolar narrowing and focal constriction
Retinal oedema
Cotton wool spots
Retinal haemorrhages and hard exudates

24

describe what signs is seen in stage 4 (acute) of hypertensive retinopathy

As for Stage 3 plus optic disc swelling

25

what changes in stage 1 and 2 happen as generalised and focal

straightening and narrowing of arterioles

26

describe all the 6 changes that are seen in stage 1 and 2 of hypertensive retinopathy

Generalised/focal straightening and narrowing of arterioles

In older px, arteriosclerosis prevents excessive narrowing = a/v ratio isn't always a accurate marker for HTN

Tortusoity

Arteriolosclerosis causes change in light reflex from vessels:
Normally see thin column of blood and longitudinal, bright reflex
Sclerosis leads to reflex becoming broader, duller and more diffuse. Vessel walls become opaque
Light reflex duller reddish brown (“copper-wire” appearance)
As sclerosis advances, reflex encompasses whole vessel and “silver wire” appearance is seen (or “sheathing”)

Crossing changes caused where underlying venule is compressed by sclerosed arteriole.
Causes ‘nipping’ (‘nicking’)

Further hardening of arteriole may cause deflection of venule, right angling, bridging may be seen.

If blood flow is impeded, may see segment of vein after crossing is larger, darker and more tortuous

27

when and why can a/v ratio sometimes not be a accurate marker for HTN

In older px = arteriosclerosis prevents excessive narrowing

28

what is the appearance of normal light reflex of the arteriole
what is the appearance with arteriosclerosis

Normally see thin column of blood and longitudinal, bright reflex

Sclerosis leads to reflex becoming broader, duller and more diffuse. Vessel walls become opaque
Light reflex duller reddish brown = copper-wire appearance

As sclerosis advances, reflex encompasses whole vessel = “silver wire” appearance is seen (or “sheathing”)

29

what is meant by:
crossing changes
nipping
deflection
bridging
segment of vein

crossing changes: caused where underlying venule is compressed by sclerosed arteriole

nipping: seen when the underlying venule is compressed by the sclerosis arteriole passing over it, gives a narrowing appearance of the vein

deflection: from further hardening of the arteriole, changes in the direction of the venule as the artery passes over it

bridging: venule has to bridge up to pass over the hardened arteriole

segment of vein: happens when blood flow is impeded, see segment of vein is larger after crossing, darker and more tortuous

30

what can severe changes at the AV crossings lead to in hypertensive retinopathy

branch retinal vein occlusion (BRVO)

31

what does the acute rise in BP seen in stage 3 and 4 hypertensive retinopathy cause and what 4 signs in the retina can this cause

Disruption of blood retinal barrier leads to increased vascular permeability (leakage of vessels)
Can cause:
Haemorrhages (often flame shaped)
Retinal oedema
Hard exudates
Deposition of hard exudates around fovea in Henles layer Macular star

32

what happens to the arteries with severe HTN (as seen in stages 3 and 4)

arteries lose ability to auto regulate and this damages capillary and arteriole vessel walls as unregulated pressure reaches small vessels

33

what can the inability of arteries to auto regulate causing damage to capillary and arteriole vessel walls in severe HTN lead to in the retina (3 signs)

May lead to:
micro aneurysms
obstruction of arterioles
and
formation of cotton wool spots (sign of retinal ischaemia)

34

what is the cause of cotton wool spots seen in stage 3 and 4 HTN

indication of disruption of axonal fluid transport as a result of retinal ischaemia

35

what gives a macula star its appearance in stage 4 hypertensive retinopathy

exudates are following the fibres of henle up the walls of the foveal pit

36

what signs in the retina indicates malignant HTN

swelling of the optic disc in addition to features in stage 3:
Retinal arteriolar narrowing and focal constriction
Retinal oedema
Cotton wool spots
Retinal haemorrhages and hard exudates

37

which retinopathy is malignant HTN associated with

stage 4 hypertensive retinopathy
characterised by the swollen optic disc

38

what do 1% of primary HTN px develop

malignant HTN

39

what 4 things can malignant HTN be rapidly fatal due to

heart failure
stroke
myocardial infarction
or
renal failure

40

list 9 symptoms a px with malignant HTN will complain of

headaches
diplopia
scotomata
dimness in vision
photopsia
chest pain
nausea/vomiting
shortness of breath
weakness

41

as well as hypertensive retinopathy, what else can be seen in patients with stage 3-4

Hypertensive Choroidopathy

42

what is hypertensive choroidopathy and what does it cause

Necrosis of choroidal vessels causes choroidal ischaemia

lack of blood supply through the choroidal circulation which results in the RPE being ischaemic = presence of yellow spots

43

what signs are seen in Hypertensive Choroidopathy

Yellow spots seen in RPE i.e. ischaemic infarcts of RPE

44

what is the sign of chronic/long term Hypertensive Choroidopathy
and what are the signs of acute Hypertensive Choroidopathy

chronic effects: Yellow spots replaced by regions of RPE pigment clumping surrounded by atrophic areas (Elschnig spots)

acute effects: Linear RPE abnormalities (Siegrist streaks) develop overlying sclerosed choroidal vessels

45

what other systemic condition has high prevalence with HTN

diabetes

because be because they share pathophysiological mechanisms e.g. inflammation, endothelial dysfunction

46

what happens if both HTN and DM is present in a px

retinopathy becomes more severe and rapidly progressive

47

how can you distinguish between the retinopathy of a patient who has both DR and hypertensive retinopathy

Hypertensive retinopathy (stage 3/4) tends to show a ‘drier’ retina than DR (R3): lots of cotton wool spots, but sparse haemorrhage, oedema, exudates

Px may have DR and hypertensive retinopathy in the same eye

48

what external ocular sign can be seen with HTN

Subconjunctival Haemorrhage = strong link with HTN

49

how many % of patients presenting with sub conjunctival haemorrhage have HTN and what must you do if you see this

~46% of patients
Advise BP check, especially if recurrent

50

what is the main management advice if you see someone with hypertensive retinopathy

Need to manage systemic hypertension

as the 3 years survival rates got lower and lower from stage 1 to 4 hypertensive retinopathy

51

what was the mortality rate of untreated malignant HTN in 2 months and in 1 year

2 months: 50%
1 year: 90%

52

how will you manage a px with stage 1 and 2 of hypertensive retinopathy

Refer to GP for investigation and management of systemic hypertension

53

how will you manage a px with stage 3 hypertensive retinopathy

Refer to GP for investigation and management of systemic hypertension
and
should also be referred for ophthalmological assessment

54

what features of stage 3 hypertensive retinopathy will resolve when treated and which feature will remain even after treatment

haemorrhage, exudate, oedema - will resolve when blood pressure reduces

Stage 1+2 features - arteriolar changes will remain

55

how will you manage a px with stage 3 hypertensive retinopathy

Is a medical emergency

Very high blood pressure will be reduced in a controlled fashion to prevent autoregulation malfunction and optic nerve head ischaemia