Essential and Secondary Hypertension (CVS) Flashcards
Define Hypertension (incl by number)
Persistently elevated arterial blood pressure
NICE says:
A clinic reading that is persistently >=140/90mmHg and 24 hrABPM/HBPM is >= 135/85mmHg
The ABPM is what confirms the diagnosis
Describe essential hypertension
Most common type (~90%)
No identifiable cause
Often linked to lifestyle factors
Describe secondary hypertension, give examples of causes
This type of hypertension is caused by an underlying medical condition such as kidney disease, thyroid problems, or sleep apnea
~10% of all cases
What are the risk factors of hypertension?
Age, Obesity, Lack of physical exercise, High salt diet, alcohol, race - black, diabetes
How common is hypertension?
Over a quarter of people in UK have it
What are the causes of hypertension (brief)
Primary HTN - no identifiable cause
Secondary HTN - Renal disease, Endocrine disorders, other causes
What are the renal causes of secondary hypertension?
- CKD e.g. due to Glomerulonephritis
- Chronic pyelonephritis
- Adult PCKD
- Renal artery stenosis
What are the endocrine causes of secondary hypertension?
- Primary hyperaldosteronism
- Phaeochromocytoma
- Cushing’s syndrome
- Liddle’s syndrome
- CAH
- Acromegaly
What are the other causes of secondary hypertension (not renal/endo)
GCCs, NSAIDs, combined oral contraceptive pill
Pregnancy, coarctation of the aorta
Most common cause of secondary hypertension?
Renal disease
What is the formula for BP?
BP = CO x TPR
HR x SV - affected by preload and contractility
TPR - vasodilation/constriction
What is the aetiology of primary hypertension (development)?
We don’t know the fundamental cause of it however there are suggested mechanisms e.g. increased/dysregulated RAAS and incr SNS
Overall, it is the result of reduced elasticity of large arteries due to elastin degradation, age related and atherosclerotic related calcification etc.
How is hypertension diagnosed incl its stages?
First, clinic reading is persistently >=140/90.
Then offer ABPM (or HBPM if intolerant to ABPM)
If <135/85 - no hypertension but monitor
If >=135/85 - Stage 1
If >=150/95 - Stage 2
What is the pathophysiology of hypertension (effects of it)?
Causes endothelial damage -> Atherosclerosis
Left vent hypertrophy
Damage to organs such as renal, cerebral, retinal
What are the clinical features of hypertension?
Usually asymptomatic
If very raised (>200/129mmHg) pts may experience headaches, visual disturbance, seizures
What are the investigations for hypertension?
24 hr BP monitor (ABPM) or HBPM if ABPM not tolerated/decline
Below is assessment for end organ damage
Fundoscopy - hypertensive retinopathy
Urine dip - renal disease e.g. if haematuria/proteinuria
ECG - LVHT or IHD
U + E blood test - renal disease
HbA1c blood - DM
Lipids blood - hyperlipidemia
What is the lifestyle management of hypertension?
Modifiable risk factors:
Weight loss, healthy diet (reduce salt/saturated fat), reduce alcohol and caffeine, reduce stress, stop smoking, exercise
What are the indications to treat for hypertension?
Indications to treat are:
Stage 1 pts who are below 80 AND have CVS disease, renal disease, diabetes or 10 year CVS risk > 10%
All stage 2 patients
What are the steps for hypertension management?
Step 1 = if under 55yrs OR diabetes, ACEi (if not tolerated e.g. cough, switch to ARB). If above 55 OR african descent, CCB
Step 2 = if step 1 failed, combine ACEi and CCB
Step 3 = Add thiazide diuretic e.g. indapamide
Step 4 = This is resistant hypertension. Either add a 4th drug or seek specialist advice.
What are the two different first line medical treatment for hypertension?
- Below 55 and end organ damage OR has diabetes - ACEi
- Above 55 or african descent - CCB
What is the management of resistant hypertension?
This is step 4.
Either
Add a fourth drug - if blood K is <4.5mmol/L then add spironolactone. If less - increase thiazide diuretic dose.
OR
Seek specialist advice
If step 4 fails, should be referred to a specialist
Features of ACEi in hypertension treatment
Age< 55 years.
This is less effective in black people so CCB is given instead
AVOID in pregnancy
Can cause a cough, then may be given ARB. Both can cause hyperkalaemia
-pril
A2RB indication to use in hypertension?
If ACEi is not tolerated usually due to cough side effect
-sartan
CCB indication in hypertension?
If above 55 yrs or african caribbean descent
- dipine
Complications of Hypertension?
Incr risk of morbidity/mortality from all causes
CAD
Heart failure
Renal failure
Stroke
Peripheral vascular disease
Hyoertensive retinopathy
Hypertensive nephropathy
CVD (particularly if high systolic)
