Hypertension Flashcards
Rationale for treatment and why?
Important preventable cause of premature morbidity and mortality
Why?
1. A symptomatic- people don’t know they have it
2. drug therapy- could cause side effects
people with hypertension are at major risk for?
- stroke- block artery supplying brain
- MI- atherosclerosis build up, thrombosis, Heart attack
- HF- high HR, afterload increase
- chronic renal failure- kidneys control this through renal output and blood flow
- cognitive decline - dementia, small vessel changes in brain ischaemia
- premature death
Hypertension facts
Increasing systolic BP by 2mmHg is associated with :
- 7% increase mortality- IHD
- 10% increased mortality from stroke
Risk factors for increased BP
- height and age
- normally distributed through population
- top of normal range there is more risk to get high and would benefit from treatment
Diagnosing suspected hypertension- clinical
Clinical BP = 140/90 or higher
quality statement for hypertension
people with suspected hypertension are offered aambulatory blood pressure monitoring (ABPM) to confirm diagnosis of hypertension
- time against BP
- every half hour and hour at night
Stages of hypertension
Stage 1
- clinic= 140/90
- ABPM-135/85
Stage 2
- clinic= 160/100
- ABPM= 150/95
What are the primary treatments for hypertension
- lifestyle modification
2. antihypertensive drug therapy
Treatments for secondary hypertension
LOOK AT PATIENT
- young person, resistant BP, signs and symptoms underlying
- reflective of another problem
- endocrine, hormonal, kidney disease
Who to offer antihypertensive treatment to stage 1 people under 80 with one of these problems:
- target organ damage- eye, heart, kidney
- established CVD
- renal disease
- diabetes
- 10+ year of cardiovascular risk over 20%
*or anyone with stage 2
goal BP to have
Under 80 - clinic <140/90, ABPM <135.85
over 80- clinic <150.90, ABPM < 145/85
Why are the elderly BP targets slightly higher?
Blood vessels lose compliance (arteries_ arteries distend (stiffer) and contract back to form secondary pulse wave,
Mechanism of BP control
Targets for therapy
- CO and periphery resistance - co= SV x HR
- interplay between
a) renin- angiotensin-aldosterone system
b) sympathetic NS - local vascular vasoconstrictor and vasodilator mediators
- peripheral resistance
Angiotensin II vasoconstrictor effects
- vascular growth
- hyperplasia
- hypertrophy - salt retention
- aldosterone release
- tubular Na reabsorption
Interfere
ACE inhibitors ARB BB renin inhibitor centralling acting ca channel blocker alpha blocker aldosterone antagonist
What are the main clinical indications of ACE inhibitors?
Hypertension, HF, diabetic and nephropathy
What are ace drugs?
Ramipril, perindopril, enalapril, trandolapril
What are sartan drugs?
same mechanism of action as ACE inhibitors, vary due to duration and cost
ARB
What are the main clinical indications for ARB inhibitors?
hypertension, diabetic and nephropathy and HF
ARB drug names
Candesartan valsartan Losartan IREsartan telmasartan
what are the main adverse effects of ARB inhibitors?
Sympotomatic hypotension hyperkalaemia potential for renal dysfunction rash angio-oedema * Contradicted in pregnancy, generally very well treated
How does ARB work?
it inhibits angiotension II to AT1 receptor
highly specific blocker
Block ACE reduce angiotensin II so substrate of enzyme increase so overcome drug effect as it competes
What are the main indications for calcium channel blockers? and the drugs you would use with each one
hypertension- amlodipine, felodipine, nifedipine, lacidipine
Ischaemic heart disease and arrhythmia- diltiazem and verapamil
attach the peripheral resistance with CCB
L type calcium channel blockers
- Dihydropyridines-: nifedipine, amlodipine, felodipine, lacidipine
- Phenylalkylamines: verapamil
- Benzothiazepines: diltiazem