Hypertension Flashcards
what is stage 1 hypertension?
clinic blood pressure of 140//90 mmHg or higher and home blood pressure monitoring blood pressure of 135/85 mmHg or higher.
what is stage 2 hypertension?
clinic blood pressure of 160/100 mmHg or higher and home blood pressure of 150/95 or higher.
what is severe hypertension?
clinic systolic blood of 180mmHg or higher or clinic diastolic blood pressure of 110 mmHg or higher.
what causes hypertension?
walls of larger arteries lose their elasticity and become rigid, and the smaller vessels constrict.
what effect does hypertension have on the brain?
- most important risk factor for stroke.
- very high blood pressure can cause a leak in a weakened blood vessel, which then bleeds in the brain (cerebral haemorrhage)
- if a blood clots blocks one of the arteries narrowed by atheroma, it can result in cerebral infarction which causes a stroke.
what effect does hypertension have on the eyes?
high blood pressure can cause one of the vessels to leak or bleed (hypertensive retinopathy) vision may become blurred due to this.
what effect does hypertension have on the heart?
- risk of myocardial infarction - if the blood flow to the heart is blocked.
- congestive heart failure (CHF) - at first the heart can compensate for the increased work of pushing against the elevated pressure in the vessels by becoming thick (hypertrophic) at a later stage the heart may no longer be able to pump enough for the heart needs.
what effect does hypertension have on the kidneys?
kidney damage - persistent high blood pressure over time can Cause narrowing and thickening of the renal arteries. this causes the kidneys to filter less fluid and results in waste in the blood.
what effect does hypertension have on the arterial tree?
- atherosclerosis - speeds up the hardening and narrowing of arteries in the body.
- aortic aneurysm - the wall of the aorta may weaken due to dilatation of the aorta with risk of rupture.
what effect does hypertension have on peripheral vascular resistance (PVR)?
PVR increases. this in turn results in further increase in blood pressure.
what is another cause of increased PVR?
atherosclerosis
what are the two types of hypertension?
essential and secondary.
what is essential hypertension?
raised blood pressure without obvious cause.
what % of cases does essential hypertension account for?
90-95%
what is essential hypertension also known as?
primary or idiopathic hypertension
what is secondary hypertension?
raised blood pressure when there is an identifiable cause
when does secondary hypertension often develop?
before the age of 35
or
after the age of 55.
what is a rare but severe type of hypertension?
accelerated hypertension
what group of people is accelerated hypertension most common in?
african-americans
what is the pathological hallmark of accelerated hypertension?
accelerated microvascular damage. the small arteries and arterioles show fibrinoid necrosis and thrombus, including those of the optic fundi and the kidneys.
what does accelerated hypertension cause?
oedema and swelling of the brain.
what would happen in the absence of effective lowering of blood pressure in accelerated hypertension?
most likely death.
what are the risk factors of hypertension?
- race - african-americans more likely.
- gender - men more likely.
- age - higher risk when old
- environment
- obesity
- diabetes
- too much salt in diet
- stress
- abnormalities in the nervous and circulatory system and kidneys
- inactive lifestyle
what does the term ‘metabolic syndrome’ describe?
a group of cardiovascular risk factors - abdominal obesity, dyslipidaemia and insulin resistance.
