|BP >140/90, has three grades
Grade 1: (mild) 140–159 and/or 90–99
Grade 2: (moderate) 160–179 and/or 100–109
Grade 3: (severe) ≥180 ≥110
Isolated systolic has a particularly bad prognosis and is associated with a 3 fold increase in mortality.
Isolated systolic hypertension:
Grade 1 140–149 <90
Grade 2 >160 <90
|BP increases with age in developed countries.
In world adult population there is 20-30% of pop with HTN
Higher incidence in black Africans (40-45% of adults)
|80-90% of patients have ‘PRIMARY’ HTN, which means essential HTN of unknown cause.
Essential HTN has a multifactorial aetiology:
Secondary HTN, is HTN due to a specific and potentially treatable cause.
|Male = worse in terms of risk factors and prognosis|
|Genetics and geography|
|Black Africans, Hispanic and Native Americans = higher incidence|
|Increases with age|
|Blood pressure measurement (HTN is usually only abnormal finding)
Consider ambulatory blood pressure monitoring.
|Made after 3 BP measurements on different occasions that are all above baseline. (caution for white coat syndrome).|
|For essential HTN it remains unclear.|
Resistance vessels (the small arteries and arterioles)
show structural changes in hypertension with an
increase in wall thickness and a reduction in the
vessel lumen diameter. It is an increased peripheral
resistance that maintains the elevated blood pressure.
The cardiac output is normal. These mechanisms would result in an increased overall peripheral vascular resistance.
Large vessel changes occur: there is thickening of
the media, an increase in collagen and the secondary
deposition of calcium. These changes result in a loss
of arterial compliance, which in turn leads to a more
pronounced arterial pressure wave.
Pulse wave velocity: A measure of arterial stiffness
and is inversely related to distensibility. With each
systolic contraction, a pulse wave travels down the
arterial wall before the flow of blood. Thus, the more
rigid the arterial wall, the faster the wave travels. It
can be measured but is not in routine use. Atheroma
develops in the large arteries owing to the interaction
of these mechanical stresses and low growth factors.
Left ventricular hypertrophy: which results from
increased peripheral vascular resistance and
increased left ventricular load, is a significant
prognostic indicator of future cardiovascular events.
vasculature lead to a reduced renal perfusion, reduced
glomerular filtration rate and, finally, a reduction in
sodium and water excretion. The decreased renal
perfusion may lead to activation of the renin-angiotensin
system with increased secretion of aldosterone and further sodium and water retention.
note: there is a 3 fold increase in the rates of cardiac death due to coronary events or cardiac failure.
Also ‘accelerated’ HTN. It is associated with the rapid onset of the above complications with the addition of rapid renal failure, heart failure, aortic dissection cerebral oedema in a risk, papilloedema and haemorrhages in the eyes. Without treatment Malignant HTN has <20% survival rate.
ARBs (f there is ace-i intolerance)
|Prognosis (with and without treatment)|
|Depends on a number of variables: