Hypertension Flashcards
The WHO define what blood pressure as hypertension?
> 140/90
What percentage of the population are hypertensive?
25%
Why are repeated BP measurements important for patients to take?
There is normal variation in blood pressure at different times of day
What are White Coat Hypertension and Labile Hypertension?
White Coat - BP high when patient has it measured by medical professional
Labile - blood pressure repeatedly or suddenly changes from normal to abnormally high levels (often during stressful situations)
What does hypertension cause, and what is it a risk factor for?
CAUSES cardiac failure
RF for: cerebral haemorrhage atheroma renal failure sudden cardiac death
Blood pressure is usually higher in black populations. TRUE/FALSE?
TRUE
What equation can be used to calculate the blood pressure?
Cardiac output (C.O.) X Peripheral Vascular Resistance
What factors can change the cardiac output?
Heart rate
Contractility
Blood Volume
What can change the peripheral vascular resistance?
Constrictors eg. Angiotensin II , Catecholamines
Dilators eg. Nitric oxide, Prostaglandins
What is thought to cause, or contribute to, Primary Hypertension?
- No obvious cause
- Genetic factors/ FHx
- Salt intake
- RAAS
- Increased Sympathetic activity
What underlying diseases can cause secondary hypertension?
- Renal disease
- Endocrine disease
- Aortic disease
- Renal artery stenosis
- Drug therapy
How can renal disease cause hypertension?
- reduces renal blood flow
=> excess renin release - salt and water overload
What endocrine disease can cause secondary hypertension?
- Adrenal gland hyperfunction/ tumours
- Conn’s syndrome - excess Aldosterone
- Cushing’s syndrome - excess corticosteroid
- Phaeochromocytoma - excess noradrenaline
What disease of the aorta can cause hypertension?
Coarctation of the aorta
- congenital narrowing of segments of the aorta
=> increased vascular resistance in these segments
Benign hypertension eventually causes what consequences in the heart and major blood vessels?
- Left ventricular hypertrophy
- Congestive cardiac failure
- Atheroma
- Aneurysm rupture (e.g. Berry aneurysms, AAA)
- Aortic dissection
- Renal disease
What happens to the heart during left ventricular hypertrophy?
- increased LV load => needs to work harder => eventually poor perfusion - interstitial fibrosis - micro-infarcts - diastolic dysfunction
What outcomes can patients experience in LV hypertrophy?
- sudden cardiac death (due to arrhythmia generating)
- cardiac failure
Rupture of a Berry Aneurysm in the brain causes what condition?
Subarachnoid haemorrhage
Even if a patient has benign hypertension, small rises in the diastolic pressure can cause a large increase in risk. TRUE/FALSE?
TRUE
Every 10mmHg of diastolic pressure above 85
=> doubles risk of MI
Every 8mmHg of diastolic pressure above 85
=> doubles risk of stroke
What is meant by microvascular injury and where does it occur?
- Blood vessel wall changes in small arteries and arterioles
- Thickening of media (smooth muscle)
- Hyaline arteriosclerosis - plasma proteins forced into vessel wall
- Occurs in Retina and kidney (common in diabetes)
What is malignant hypertension?
- Diastolic pressure >130-140
When does malignant hypertension occur?
- develops from either benign primary or secondary hypertension (‘accelerated’ hypertension)
- Can arise de-novo
What consequences can be caused by malignant hypertension?
- cerebral oedema - seen as papilloedema
- Acute renal failure
- Acute heart failure
- Headache and cerebral haemorrhage
How does malignant hypertension acutely affect blood vessels?
- fibrinoid necrosis
- endarteritis proliferans of their walls
