Hypertension Flashcards
Why is screening for hypertension important
Hypertension is often symptomless
What can result for hypertension
Major cause of premature vascular disease, leading to cerebrovascular events, ischaemic heart disease and peripheral vascular disease.
Increased blood pressure means increased mortality rates
Epidemiology of hypertension
Men
>35
Major risk factor for CVD
Under treated, under diagnosed and poorly controlled in UK
What is considered normotensive
less than 140/90mmHg
What are the stages of hypertension
Stage 1 hypertension
Stage 2 hypertension
Severe hypertension
What classifies as Stage 1 hypertension
Equal to or >140/90mmHg
Daytime average Ambulatory blood pressure monitoring (ABPM - 24hr BP monitor) or Home blood pressure monitoring (HBPM); Equal to or >135/85mmHg
What classifies as Stage 2 hypertension
Equal to or >160/100mmHg clinic BP
Daytime average ABPM or HBPM Equal to or >150/95mmHg
What classifies as Severe hypertension
Clinic systolic BP Equal to or >180mmHg and/or
diastolic BP Equal to or >110mmHg
Start immediate anti-hypertensive drug treatment!
What is the most common cause of atherosclerosis and cerebral haemorrhage
Hypertension
How can you classify the causes of hypertension
Unknown - Essential (primary or idiopathic) hypertension (most cases)
Known - Secondary hypertension
Essential hypertension is multifactorial - give examples of things that can contribute to the disease
- Genetic susceptibility
- Excessive sympathetic nervous system activity
- Abnormalities of Na+/K+ membrane transport
- High salt intake
- Abnormalities in renin-angiotensin-aldosterone system
Causes of Secondary hypertension
Renal disease
Pregnancy
Other potential underlying causes:
Endocrine causes, Coarctation of aorta, Drug therapy
What is most common cause of secondary hypertension
Chronic Kidney Disease
What is the most common cause of chronic kidney disease
Diabetes
How can renal disease be exacerbated by hypertension
Hypertension accelerates atherosclerosis and endothelial cell dysfunction, promoting pheochromocytoma vasoconstriction - this can cause or exacerbate renal disease
Endocrine causes of secondary hypertension
Cushings syndrome
Conn’s syndrome
Pheochromocytoma
How does Cushings cause hypertension
Hypersecretion of corticosteroids (which enhance adrenalines resulting in a vasoconstrictive effect) is associated with systemic hypertension
How does Conns cause hypertension
Adrenal tumour that secretes ALDOSTERONE (resulting in Na+ retention and thus water retention thereby increasing blood volume and pressure) can cause hypertension
How does Pheochromocytoma cause hypertension
Adrenal tumour that secretes CATECHOLAMINES (resulting in the stimulation of alpha-adrenergic receptors resulting in vasoconstriction, increased cardiac contractility as well as the stimulation of beta-adrenergic receptors resulting in an increase in heart rate and contractility) can cause hypertension
Describe presentation of hypertension in coarctation of aorta (systemic hypertension is one of most common features of coarctation)
Raised blood pressure will be detected in either arm, but NOT in the legs
The femoral pulse is often delayed relative to the radial
Untreated or undiagnosed patients with coarctation of aorta with hypertension can die from..
CF
Hypertensive Cerebral Haemorrhage
Dissecting aneurysm
Prescription drugs that can cause hypertension
Corticosteroids e.g. Prednisolone
Cyclosporin
Erythropoietin
Some types of the contraceptive pill
Non-prescription drugs that can cause hypertension
Alcohol
Amphetamines
Ecstasy
Cocaine
Risk Factors for hypertension
- Age (risk increases as you age)
- Race - hypertension is more common in blacks
- Family history (hypertension runs in families)
- Overweight and obese
- Little exercise
- Smoking
- Too much salt in diet
- Alcohol
- Diabetes
- Stress
Hypertension: Vascular Changes
- Hypertension accelerates atherosclerosis
- Thickening of the media of muscular arteries
- It is the smaller arteries and arterioles that are especially affected in hypertension
- *The resulting endothelial cell dysfunction is associated with impaired nitric oxide-mediated vasodilatation and enhanced secretion of vasoconstrictors including endothelins and prostaglandins
Hypertension: Heart damage that could result
Hypertension is a major risk factor for ischaemic heart disease
Hypertension: Nervous system damage that could result
Intracerebral haemorrhage is a frequent cause of death in hypertension
Hypertension: Kidneys damage that could result
Hypertension can cause or result from renal disease
Kidney size reduced
Smaller vessels show intimal thickening and medial hypertrophy
Numbers of sclerotic glomeruli are increased
Describe Malignant hypertension in body
Markedly raised diastolic blood pressure, usually over 120mmHg and progressive renal disease.
Renal vascular changes
Acute haemorrhage
Papilloedema (optic disc swelling due to raised inter cranial pressure)
Who can get malignant hypertension
Can occur in previously fit individuals
Often black males in their 30-40s
Consequences of malignant hypertension
- Cardiac failure with left ventricular hypertrophy and dilatation
- Blurred vision due to papilloedema and retinal haemorrhages
- Haematuria and renal failure due to fibrinoid necrosis of glomeruli
- Severe headache and cerebral haemorrhage
Clinical presentation of hypertension
Usually asymptomatic (except malignant hypertension) Found on screening
Diagnosis of hypertension
End-organ damage e.g. left ventricular hypertrophy, retinopathy and proteinuria (indicates severity and duration of hypertension and associated with a poorer prognosis)
Urinalysis: protein/albumin:creatine ratio and haematuria
Blood tests
Fundoscopy/Opthalmscopy (looking for retinal haemorrhage or papilloedema)
Echocardiography or ECG: LV hypertrophy
24 hour ambulatory BP monitoring
What would you look for on blood tests of hypertension
Serum creatinine
eGFR
Glucose (to assess diabetes risk)
What is the goal BP from treatment of hypertension
140/90mmHg
Non- drug treatment of hypertension
Change diet: High consumption of vegetable and fruits and low-fat diet Regular physical exercise Reduce alcohol intake Reduce salt intake Lose weight Stop smoking
Pharmacological treatment of hypertension
ACD pathway:
A - ACE-inhibitor e.g. Ramipril or Enalapril
C - Calcium channel blocker (CCB) e.g. Nifedipine or Amlodipine
D - Diuretics e.g. Bendroflumethiazide (thiazide, distal tube - less potent) or Furosemide (loop diuretic, loop of henle - more potent)
If patient has coughing issues, what would you give instead of the contra-indicated ACE-inhibitor for treating hypertension
Angiotensin Receptor Blocker (ARB) e.g. Candesartan or Losartan
When would you consider Beta-blocker as treatment for hypertension
Not first line treatment
Consider in young people especially if intolerant to ACEi/ARB
In people where higher dose of drugs not tolerated
What drugs would you give to patients <55 yrs old to treat their hypertension
Ramipril/Candesartan \+ Nifedipine \+ Bendroflumethiazide \+ Furosemide (in stages?)
What drugs would you give to patients >55 yrs old/black/African-Carribean origin to treat their hypertension
Ramipril/Candesartan + Nifedipine
+ Bendroflumethiazide
+ Furosemide
(3 stages)
What is essential hypertension
Hypertension with primary cause unknown
How does size of kidney change with hypertension
Reduces
*Investigations and their results
Urinalysis - protein; albumin:creatinine ratio; haematuria
Blood tests - serum creatinine
Fundoscopy/ophthalmoscopy - papilloedema
ECG - LV hypertrophy
