DIS - Diseases of the Vasculature III: Hypertension - Week 11 Flashcards
Define the following: Essential/primary hypertension Borderline Normotensive How many readings are required?
Essential -BP >160/95mmHg Borderline -BP 140/90 to 160/95 Normotensive -BP <140/90 3 readings on separate occasions
What diastolic BP is considered too high and worthy of reducing?
Anything over 100mmHg (in general)
List four things BP is considered in relation to.
Serum cholesterol
Race
Age
Family history
Define malignant hypertension. What is it associated with and in what two organs?
> 120mmHg diastole
Associated with exudative vasculopathy in the retina and kidney
What percentage of hypertension cases are secondary?
5%
What two types of conditions cause secondary hypertension? Give some examples for each.
Renal conditions
-nephritis, renal failure, tumour
Endocrine conditions
-diabetes, hyperthyroidism, parathyroidism
What five things is the degree of BP an accurate predictor of?
Coronary artery occlusion Stroke Renal failure Heart failure Peripheral vascular disease
Is there some risk of pathology even at normal blood pressures?
Yes
List three things that can happen to the brain due to hypertension.
Atherosclerotic/endarteritic damage to cerebral vessels
TIA
Stroke
List two things that can happen to the kidney due to hypertension.
Enarteritic changes in the renal bed
Ultimate renal failure from sclerosis
List two things that can happen to the heart due to hypertension.
Left ventricular hypertrophy - cardiac failure
BP damage to cardiac vessels - myocardial infarction
Do patients with similar blood pressure have similar or different ocular signs?
Different - variable relatinoship between measured blood pressure and retinopathy
What percentage of hypertension patients have a normal fundus?
~1/3
Why does constriction of arterioles occur with hypertension and what is it in response to exactly (2)?
Lumen narrows to maintain blood flow as perfusion pressure drops
-autoregulation to decreased peripheral resistance
What are two consequences of constricted arterioles on the retina (fundus appearances)?
Attenuation
Focal constriction
How does arteriolar sclerosis affect vessel wall transparency? What fundus appearance does this give?
Loss of transparency
-increased reflex and copper wiring
Does arteriolar sclerosis cause lumen narrowing? What fundus appearance does this give?
Yes
-nicking
What happens to veins at AV crossings due to arteriolar sclerosis? What fundus appearance does this give?
Deflection
-right angle Xing
How is the lumen of veins affected by arteriolar sclerosis? What fundus appearance does this give?
Compression
-banking
List three signs of first degree hypertension. Describe its clinical significance.
Focal arteriolar constriction
Banking (a form of crossing change)
Isolated flame haemorrhage
Lower clinical significance
Is first degree hypeltension related to accelerated or non-accelerated blood pressure?
Non-accelerated
List five signs of second degree hypertension. Describe its clinical significance.
Numerous flame haemorrhage Retinal lipid/exudate Cotton wool patches Retinal vessel occlusion Papilloedema
Is second degree hypertension related to accelerated or non-accelerated blood pressure?
Accelerated
List the four grades of hypertension according to the wong and mitchell grading system for hypertensive retinopathy.
No retinopathy
Mild retinopathy
Moderate retinopathy
Malignant retinopathy
List four signs suggestive of mild hypertensive retinopathy.
One or more of the following Generalised arterial narrowing Focal arterial narrowing AV nicking Silver wire
List four signs suggestive of moderate hypertensive retinopathy.
One or more of the following Haemorrhage (dot/blot/flame) Microaneurysm Cotton wool spots Hard exudates
List two requirements for malignant hypertensive retinopathy.
Moderate retinopathy signs plus optic disc oedema
Within how many disc diameters are focal arteriolar constrictions most readily seen? How does it appear on funduscopy?
1-2DD of the disc
Alternating zones of passive dilation and spasm
Does the presence of focal arteriolar constriction have good or poor sensitivity and specificity for systemic hypertension?
Good for both
Comment on the presence of banking in terms of hypertension possibility.
A reliable guide to possibility of hypertension
Where is banking commonly seen?
AV crossings
Describe how banking appears and what it means.
Restriction of venous return
Upstream dilation of the vein
-distal vein calibre > proximal side
What does banking indicate?
Significant interruption to venous blood flow
What does banking increase the risk of (3)?
Thrombus formation (eventual venous occlusion) Vein's endothelium may become sticky Risk of platelet adhesion to walls
What may bypass banking?
Shunt vessels
Is hypertension a common cause of flame haemorrhage?
Yes
What is a flame haemorrhage? Where does blood run along?
Leakage of superficial capillaries into the NFL
-seepage along axon bundles