Hypertension – pathophysiology, presentation and investigation Flashcards
(44 cards)
What is the definition of hypertension
the blood pressure above which the benefits of treatment outweigh the risks in terms of morbitdity and mortality
Sustained hypertension is a contributing risk factor to
end-organ damage to blood vessels, heart and kidney
Increasing blood pressure is associated with a progressive exponentially increase in the risk of
Stroke
Heart disease
As well as increasing high blood pressure what also increases the risk of stroke and heart disease
Increasing age
What is normal blood pressure
systolic pressure of 120–129 mmHg or a diastolic pressure of 80–84 mmHg
What is stage 1 hypertension according to NICE
Clinic blood pressure is 140/90 mmHg or higher
ABPM daytime average 135/85 mmHg or higher.
What is stage 2 hypertension according to NICE
Clinic blood pressure is 160/100 mmHg or higher
ABPM daytime average 150/95 mmHg or higher.
What is severe hypertension according to NICE
Clinic systolic blood pressure is 180 mmHg or higher or diastolic blood pressure is 110 mmHg or higher.
What is Ambulatory Blood Pressure Monitoring (ABPM)
when your blood pressure is measured as you move around, living your normal daily life. It is measured for up to 24 hours
How is ABPM more efficient
Gives a more realistic blood pressure, as measured throughout the day rather than one reading
What is the two aetiologies of hypertension
Primary hypertension - no unknown cause
Secondary hypertension - underlying cause
What is the proportion of primary hypertension and secondary hypertension
Primary = 90% Secondary = 5-10%
What is the aetiologies of secondary hypertension
Renal disease Drug induced pregnancy endocrine diseases Vascular diseases sleep apnoea
What increases the risk of hypertension development
Cigarette smoking Adds 20/10 mmHg Diabetes mellitus 5-30 X increase MI Renal disease Male 2X risk Hyperlipidaemia Previous MI or stroke Left ventricular hypertrophy 2X risk
What are the prime contributors to blood pressure than can be manipulated by drug therapy
Cardiac output
-Stroke volume
-Heart rate
Peripheral vascular resistance
What controls blood pressure
An integrates system ( SNS + RAAS)
What system is needed in log term control of BP
Renin angiotensin aldosterone system
What is RAAS responsible for
maintenance of sodium balance
therefore controlling blood volume
which in turn controls blood pressure
What is RAAS stimulated by
fall in BP
fall in circulating volume
sodium depletion
what is the result of stimulated RAAS
Renin released from juxtaglomerular apparatus
Renin converts angiotensinogen to angiotensin I
Angiotensin I is converted to angiotensin II by angiotensin converting enzyme (ACE)
What is the function of angiotensin II
vasoconstrictor
anti-natriuretic peptide
stimulator of aldosterone release from the adrenal glands
What does it means that angiotensin is a potent hypertrophic agent
stimulates myocyte and smooth muscle hypertrophy in the arterioles
What is the negative outcomes of angiotensin II being a potent hypertrophic agent
Arteries become narrower and cant dilate,
Unable to repsond to appropriate dilation
therefore more likely to split and become damaged
What controls short term effect of blood pressure
Sympathetic NS
