hypertension 1&2 Flashcards
define hypertension
sustained or persistent elevated arterial BP
what effects hypertension?
age, gender, race
is hypertension bimodal?
no, it is normal among BP population
what is normotensive and hypertensive?
normotensive- normal blood pressure
hypertensive- high blood pressure
what is the 2 things hypertension is based on?
associated CV risk
based on arbitrarily defined ‘normal’ BP levels
what does NICE define as hypertensive?
140/90mmHg
what does ACC/AHA define as hypertensive?
130/80 mmHg
what ways does misdiagnosis usually occur?
Poor sensitivity & specificity
‘White coat’ hypertension phenomenon
what do NICE recommend in order to avoid misdiagnosis?
Multiple clinic/office BP measurements >140/90 mmHg
Ambulatory BP monitoring (ABPM) orHome BP monitoring (HBPM) >135/85 mmHg
how is hypertension classified?
according to blood pressure level( moderate to severe)
traditional 1-3
nice stages 1-3
when does CVD risk double?
doubles with each BP increment of 20/10 mm Hg
what does target organ damage cause?
Cerebrovascular disease Hypertensive retinopathy Left ventricular dysfunction Coronary artery disease Peripheral artery disease chronic kidney disease
how is hypertension categorized based on the aetiology?
hypertension w/ known causes (secondary 5-10%)
hypertension w/ unknown causes(primary 90-95%)
what are the 4 secondary causes of hypertension?
renal/endocrine/pregnancy/ drugs
what does primary hypertension cause?
increase in total peripheral resistance
Hyper-reactivity of BP to stress, abnormal vascular reactivity & impaired circulatory homeostasis
is hypertension a disorder?
yes its a disorder or a syndrome
what are the 3 things that control BP?
cardiac output
peripheral resistance
blood volume
what are 4 sites of blood pressure control?
1-resistance arterioles
2-capacitance venules
3-pump output heart
4-vol in kidneys
what are the major postulates of pathogenesis mechanisms?
role of:genetics/ kidney/vascular reactivity and remodelling/neurohormonal factors/central and sympathetic NS
what kind of risks are there?
modifiable- e.g. diet
non- modifiable- e.g. genetics
why do you treat hypertension?
to target organ damage
associated with CV mortality
lowering BP reduces CV mortality
for treatment, what is the goal for maintaining BP?
> 140/90 mmHg (office/clinic)or>135/85 mmHg (ABPM/HBPM)for all adults under 80 years old
150/90 mmHg (office/clinic)or>145/85 mmHg (ABPM/HBPM)for adults 80 years old and over
what are the 6 pharmacological treatments for hypertension?
ACE Inhibitors (ACEIs) Angiotensin II receptor antagonists (ARBs) Calcium channel antagonists Diuretics b-Adrenoceptor antagonists (b-blockers) Miscellaneous
what are the aims of non-pharmacological therapy?
to help lower BP
to control other risk factors
to help reduce doses of other hypertensive drugs
what are the 5 steps of modification of lifestyle?
1- weight reduction 2- dash eating plan 3- dietary na+ reduction 4-physical activity 5-alcohol moderation
what are the main mechanisms for lowering BP?
decrease plasma volume
decrease total peripheral resistance (TPR)
decrease cardiac output (CO)
or combinations of three mechanisms
what is ACEIs mechanism of antihypertensive effect?
dec angiotensin II production dec vasoconstriction dec PVR
dec aldosterone secretion dec fluid retention dec PV
dec sympathetic activation dec vasoconstriction dec PVR
these in turn inc bradykinin and PGI2 synthesis
what is ACEIs first choice initial therapy for?
younger hypertensive patients (55 years old) of non-African or Caribbean descent
All diabetic patients, irrespective of age or ethnic origin
what is the mechanism for ARBs?
reduction of BP via AT1-receptor blockade
dec vascular AT1-R activation dec vasoconstriction dec PVR
dec aldosterone secretion dec fluid retention dec in PV
decsympathetic activation dec vasoconstriction dec PVR
initial use of ARBs when:
younger hypertensive patients (55 years old) of non-African or Caribbean descent
All diabetic patients, irrespective of age or ethnic origin
what is ARBs effective in combination with?
effective combination with CCBs & thiazide-type diuretics
how do CCBs produce their antihypertensive effect?
reduction of BP viablock of Ca++influx into heart cells and/or blood vessels
CCBs are first line when:
elderly hypertensive patients (aged 55 and over)black (African/Caribbean) patients of any age
what are CCBs effective in combination with?
CEIs, ARBs, BBs & thiazide-type diuretics
how do diuretics produce their antihypertensive effect?
reduction of BP via:
- increased diuresis-reduced plasma volume and decrease in CO
- reduced peripheral vascular resistance(vasodilation/ NA stores)
how much can diuretics lower BP by?
10-15mmHg
what are the main dose of diuretics given?
low dose thiazide & thiazide-like agents used
diuretics recommended for an ALTERNATIVE first choice when
elderly hypertensive patients (aged 55 and over)
black (African/Caribbean) patients of any age
diuretics effective when given with:
AEIs, ARBs & CCBs
what is the mechanism for antihypertensive effect for B-adrenoceptor antagonists?
unsure... postulate mechanisms: reduction of CO inhibition of renin release modulation of central BP regulation resetting of baroreceptors readjustments of blood flow
what are the initial effects of b-adrenoceptor antagonists?
decrease in BP due to decrease in CO
PRV may increase slightly
what are the chronic effects of antihypertensive action?
CO may or may not return to normal sustained reduction in PVR decrease BP
how much can b-adrenoceptors reduce BP by?
15-20%
when are b-adrenoceptors an effective therapy?
combination with DH-type CCBs
