PBL 6 - hypertension Flashcards
what is classified as hypertension at home vs in office?
home = >130/85 office = > 140/90
why are out of office BP measurements recommended to confirm the diagnosis of hypertension?
- can be a big difference in office and home BP measurements
- white coat syndrome
- monitor the quality of BP control
- reduce chances of misdiagnosing anxious people and treating them with unnecessary drugs
does smoking affect BP?
smoking itself does not raise BP, but the combination of high BP and smoking is lethal — accelerates atherosclerosis
does BP change as you age?
increases naturally as you get older
what level of alcohol intake is associated with an elevation of BP?
male > 28 units a week
female > 21 units per week
what is the definition of hypertension?
an increase in peripheral vascular resistance when the cardiac output is normal
an increase in BP increase the risk of what?
ishcaemic heart disease
what is primary (essential) hypertension and what % of cases are primary?
- hypertension when it is not a result of a medical condition or drug (doesn’t have a known secondary cause)
- 98%
name some medical conditions which cause secondary hypertension
- chronic kidney disease
- primary hyperaldosteronism
- renovascular disease
- chronic steroid therapy
- cushing’s syndrome
- aortic coarctation
- thyroid or parathyroid disease
- sleep apnea
- pheochromocytoma (tumour from chromaffin cells — make adrenaline and noradrenaline, found in adrenal gland)
describe primary hyperaldosteronism (Conn’s Syndrome)
- excess production of aldosterone from adrenal gland — more Na+ retention and hence H2O retention — increases BP
- can cause secondary hypertension
- low prevalence
- 30% caused by adrenal adenoma
- adenomata commoner in women and rare in children
- 70% caused by adrenal hyperplasia — both adrenal glands are overactive
- rarely adrenal carcinoma
- extremely rare glucocorticoid suppressible aldosterone so (autosomal dominant) — only seen in specialist clinics
describe renovascular disease
- fibromuscular dysplasia of the renal artery — often in very young patients, teenagers and early 20s
- renal artery stenosis in older patients due to atherosclerosis
- both can be cured with angioplasty and stenting (although in renal artery stenosis the patients have to be highly selective)
what is the most likely cause of primary hypertension?
autonomic neural dysfunction — over active SNS in combination with an under active PNS
name 7 environmental factors that contribute hypertension
- inactivity
- stress
- obesity
- tobacco
- age
- salt
- alcohol
name 3 characteristics of hypertension
- increased peripheral vascular resistance
- normal cardiac output
- damage to vital organs
how does hypertension cause LV hypertrophy?
heart has to beat against the increased vascular resistance — increase in workload — hypertrophy of the LV
how does high BP affect the kidneys?
- kidneys become granular and shrunken
- leak proteins
- gradually fail
risk of CHD is always higher with what?
left ventricular hypertrophy
what are some signs that suggest secondary hypertension and organ damage?
- features of cushing syndrome
- skin stigmata of neurofibromatosis (phaeochromocytoma)
- palpation of enlarged kidneys (polycystic kindey disease)
- auscultation of abdominal murmurs (renovascular hypertension)
- auscultation of precordial or chest murmurs (aortic coarction or aortic disease)
- diminished and delayed femoral and reduced femoral BP (aortic coarction, aortic disease)
signs of organ damage in the brain?
murmurs over neck arteries (atherosclerosis in carotids), motor sensory defects
signs of organ damage in retina?
funduscopic abnormalities (looking for haemorrhages and exudates — severe hypertension)
signs of organ damage in heart?
- location: enlargement of heart — LVH
- characteristics of apical impulse: displaced apex beat — heart beginning to fail
- abnormal cardiac rhythms
- ventricular gallop (3rd heart sound — suggests HF)
- pulmonary rales (small bubbly, rattling sounds in the lungs — sign of HF)
- dependent oedema
signs of organ damage in peripheral arteries?
- absence, reduction or asymmetry of pulses
- cold extremities of ischaemic lesions (suggesting peripheral vascualr disease as a result of hypertension)
what are some lifestyles that should be considered/adopted to reduce BP?
- smoking cessation
- weight reduction
- reduction of excessive alcohol intake
- physical exercise
- reduction of salt intake
- increase in fruit and vegetable intake and decrease in saturated and total fat intake
what is renal denervation?
= a minimally invasive procedure to treat resistant hypertension
- catheter into renal artery
- raise temperature
- destroy the sympathetic nerves in the vascular wall
- strong placebo effect — unpopular treatment
- research ongoing
what is first prescribed to treat hypertension in someone aged under 55 years and not of African or Caribbean origin?
ACE inhibitor or low-cost angiotensin II receptor blocker (ARB)
what is first prescribed to treat hypertension in someone aged 55 years or black person of African or Caribbean origin of any age?
calcium-channel blocker (CCB)
what is the second line of hypertension treatment?
ACE inhibitor or ARB plus a calcium-channel blocker
what is the third step of treatment for hypertension?
ACE inhibitor/ARB + CCB + thiazide-like diuretics
how do you treat resistant hypertension (step 4)?
- ACE inhibitor/ARB + CCB + thiazide-like diuretic + further diuretic or alpha/beta-blocker
- consider referral to specialist centre for further investigation
