Hypertension Flashcards
Define hypertension
a disorder in which the level of sustained arterial pressure is higher than expected for the age, sex, race of the individual
State the WHO value for hypertension
>140/90
What does hypertension cause?
cardiac failure
What is hypertension a risk factor for?
- cerebral haemorrhage - atheroma - renal failure - sudden cardiac death
BP= ?x?
cardiac output x peripheral resistance
What determines cardiac output?
- heart rate - contractility - blood volume
What determines peripheral resistance?
- constrictors - dilators
Describe primary hypertension
Accounts for 90% of cases No obvious cause, usually genetic. Related to salt, protein, RAA & sympathetic activity
State five diseases that cause secondary hypertension
- renal disease
- endocrine disease
- aortic disease
- renal artery stenosis
- drug therapy
How do renal causes lead to hypertension?
Reduced renal blood flow, excess renin release & salt/water overload
Name four endocrine causes of hypertension
- Adrenal gland hyperfunction/tumours
- Conn’s syndrome - excess aldosterone
- Cushing’s - excess corticosteroid
- Pheochromocytoma - excess noradrenaline
Give example of other causes of secondary hypertension
Drugs, coarctation of the aorta, sleep apnoea
What does benign hypertension eventually cause?
- LV hypertrophy - congestive cardiac failure - increased atheroma - increased aneurysm rupture - renal disease - stroke
Describe left ventricular hypertrophy
Increased LV load, poor perfusion, interstitial fibrosis, micro-infarcts, diastolic dysfunction leads to arrhythmias and cardiac failure
Describe microvascular injury
blood vessel wall changes in small arteries & arterioles retina and kidney blood vessel damage, tunica media thickens
Name A, C & D
A - ACE inhibitor/ARBs
C - Calcium channel blocker
D - Thiazide - like diuretic
