Hypertension Flashcards
Outline how an increase in BP is reversed
Detected by baroreceptors in carotid sinus and aortic arch
Stimulate cardioinhibitory centre and inhibit cardiostimulatory and vasomotor centre
Decrease SNS decreasing HR, contractility and CO. Decreased vasomotor causes vasodilation
Overall less resistance and cardiac output drops BP
Outline how a drop in blood volume and therefore blood pressure is reversed
Drop in blood pressure detected by juxtaglomerular cells, causing an increase in renin, which reacts with angiotensinogen (liver) to produce angiotensin I, which reacts with ACE (lungs) to produce angiotensin II, which causes vasoconstriction and the adrenal cortex to release aldosterone, which increases the kidneys Na+ and H2O reabsorption to increase blood volume
Define hypertension
Transitory or sustained elevation of systemic arterial blood pressure to a level likely to induce cardiovascular damage or result in other adverse health consequences
What are modifiable risk factors for hypertension?
Diet, tobacco, physical inactivity, alcohol
What is stage 1 and stage 2 hypertension?
140-159/90-99 lifestyle and drugs
>160/100 lifestyle and 2 drugs
What are the two types of hypertension?
Primary/essential - 95% - idiopathic
Secondary - 5% - a (possibly) rectifiable underlying cause
What are possible symptoms of hypertension?
Headache, dizzy, palpitation, fatigue, blurred vision
What are the consequences of hypertension?
CVD risk
Damage to CVS, kidney, nervous system and eyes
What is the effect of a 5 and 10 increase in diastolic BP on stroke and CHD?
34% 57%
21% 37%
What can happen in the systems damaged by hypertension?
CVS - atherosclerosis, CAD, aneurysm, dissection, LV hypertrophy and heart failure
Kidney - glomerular sclerosis and Ischaemic disease
CNS - stroke, haemorrhage, cerebral atrophy, dementia
Eyes - retinopathy, haemorrhage, neuropathy (paralyse)
What signs may be seen in the eyes and how do they occur?
Haemorrhage, exudates and cotton spotting
Arteriolar narrowing, AV nicking, the above, papilloedema
What is the prevalence (M+F) of HTN %
33m
29f
What is the effect of exercise on BP?
Reduce by 13/4
What is the acute effect of exercise on hypertension?
Post exercise hypotension (10) due to baroreflex set point lowered and TPR reduced by 25%
Can last 24 hours
What is the chronic effect of exercise on hypertension?
Reduce SNS
Increase vascular responsiveness
Structural adaptations - increase length and CSA and increase angiogenesis
