Hypertension Flashcards
What is hypertension?
A blood pressure at which the benefits of treatment with an antihypertensive agent reduces cardiovascular, cerebrovascular and peripheral vascular risk outweigh the risks.
What is the blood pressure that classifies hypertension?
140/90mmHg
What % of the adult population is affected by hypertension?
30-40%
An increase in Blood pressure of 20 mmHg systolic or 10 mmHg diastolic above the ideal _________ the risk of cardiovascular death, regardless of age.
Doubles
What happens to the risk of cardiovascular disease and stroke as blood pressure increases?
Risk increases exponentially
What is the clinic and ambulatory blood pressure associated with stage 1 hypertension?
140/90mmHg clinic
135/85mmHg ambulatory
What is the clinic and ambulatory blood pressure associated with stage 2 hypertension?
160/100mmHg clinic
150/95mmHg ambulatory
What is the clinic blood pressure associated with severe hypertension?
180/120mmHg or higher
What is the difference between primary and secondary hypertension?
Primary hypertension has no known cause
Secondary hypertension occurs secondary to a known condition/cause
Which is more common- primary o secondary hypertension?
Primary (80-90% of cases)
What are some of the causes of secondary hypertension?
ROPE
R- Renal disease (renal artery stenosis, polycystic kidneys, chronic pyelopnephritis and fibromuscular dysplasia)
O-Obesity
P- Pregnancy
E- Endocrine disorders (hyperaldosterinism and cushings)
Also, coarctation of the aorta, sleep apnoea and drugs can induce hypertension (NSAIDS, combined pill and corticosteroids),
What is the number 1 cause of medical death worldwide?
Hypertension
List the 7 risk factors associated with hypertension
- Smoking
- Diabetes mellitus
- Renal disease
- Male
- Hyperlipadaemia
- Previous MI or stroke
- Left ventricular hypertrophy
List the two physiological factors that the body uses to control blood pressure
- Cardiac output
2. Peripheral vascular resistance
What are the two main targets of antihypertensive drugs?
the sympathetic nervous system and the RAAS
What are the two most likely pathophysiological causes of hypertension?
- Increased reactivity of resistance vessels and resultant increase in peripheral resistance as a result of an hereditary defect of the smooth muscle lining arterioles
- A sodium homeostatic effect. In hypertensive individuals the kidneys are unable to excrete appropriate amounts of sodium for any given blood pressure. As a result, sodium and fluid are retained and the blood pressure increases
Explain why blood pressure rises with age
The elasticity of the vessels is lost and so arteries become less complaint
Can hypertension be hereditary?
Yes
Explain the environmental factors that can cause hypertension
Mental and physical stress
What is the most important non-pharmacological intervention in hypertensive patients?
Weight loss
Explain how birth weight impacts on hypertension later in life
The lower the birth weight the higher the likelihood of developing hypertension and heart disease in adulthood
What % of the population is affected by alcohol induced hypertension?
1%
Which race is most likely to develop hypertension?
African
Which hypertension presentations (5) point towards secondary hypertension rather than primary hypertension?
- The hypertension is severe or resistant
- If the patient is a child / adolescent
- If there is a worsening of previously stable hypertension
- If the hypertension is malignant
- If no other risk factors are identified and the patient is <30 years old
Which investigations should be conducted if secondary hypertension is suspected?
- Renal function tests and urinalysis
- Renal imaging (MRI arteriography and ultrasound)
- Aldosterone to renin ratio (ARR) to look for excessive aldosterone production (caused by adenoma of the adrenal glands)
- 24h urine for catecholamines / metanephrines looking for a phaeochromocytoma or paraganglioma
What is the second most common cause of maternal and fetal death?
Hypertension in pregnancy
if a woman has gestational hypertension, when did the hypertension begin?
The patient had a normal blood pressure before pregnancy but develops hypertension during pregnancy.
What is the difference between gestational hypertension and pre-eclampsia
In gestational hypertension there is no evidence of proteinuria whereas in preeclampsia proteinuria is present
What impact does gestational hypertension or preeclampsia have upon a womans risk of cardiovascular disease later in life?
It increases the risk of CVD later in life
Define the term “hypertensive emergency”
A severely elevated BP (BP>180/120 mmHg) with evidence of acute target organ damage
What are the rules regarding lowering the blood pressure of a patient with a hypertensive emergency/
In everyone except acute ischaemic stroke and aortic dissection, the aim is to lower systolic blood pressure by 10- 20% within the first hour (DO NOT LOWER ANY FASTER!) and then to 160/100mmHg over the subsequent 6 hours
Why must the blood pressure be lowered slowly in a patient with a hypertensive emergency?
a more aggressive and rapid lowering of blood pressure is associated with an increase in morbidity and mortality
What is the next step in managing a hypertensive emergency once blood pressure has reached the target range?
the patient should start oral therapy and begin to wean away from the IV medications over the following 12-24 hours.
What are the ONLY 2 indications for rapid blood pressure lowering in a patient with a hypertensive emergency?
Ischaemic stroke and aortic dissection
What should the systolic blood pressure be lowered to in a patient with a hypertensive emergency and an aortic dissection?
Systolic 100-120mmHg
What type of drug should NEVER be given to a patient suffering from a hypertensive emergency and why?
NEVER START AN ACE INHIBITOR OR A ARB IN PATIENTS WITH A HYPERTENSIVE EMERGENCY! THEY WILL SIGNIFICANTLY DAMAGE KIDNEY FUNCTION IN THIS SITUATION.
Define hypertensive urgency
- Severely elevated blood pressure with NO evidence of acute target organ damage is described as hypertensive urgency (a step down from emergency)
Do patients with hypertensive urgency need to be admitted to hospital?
No- they can be started on dual oral therapy and assessed after 24 hours.
Define orthostatic hypotension
a blood pressure decrease of 20 mmHg systolic and/or a diastolic pressure of 10 mmHg within three minutes of standing.
What is orthostatic hypotension strongly associated with?
Hypertension
What are the risks associated with orthostatic hypotension?
- Syncope
2. Increased cardiovascular risk
What are the 5 main causes of orthostatic hypotension?
- Ageing
- Diabetes
- Antihypertensive drugs
- Auto-immune systemic diseases
- Neurological syndromes: pure autonomic failure, multiple system atrophy, Parkinson’s disease
What non-pharmacological methods can be used to manage orthostatic hypotension?
Teach the patients manoeuvres which either mobilise blood volume from the lower parts of the body or stimulate pressure receptors leading to vasoconstriction 9e.g. heel rising or isometric handgrips)
Tilting the patients bed into a heads up position
What is the only drug currently licenced for use in orthostatic hypotension in the UK, how does it work and what is its associated contra-indication?
Midodrine
It is an orally administered α1-adrenoreceptor agonist which constricts arteriolar and venous capacitance vessels, increasing peripheral vascular resistance.
The action of this drug may worsen pre-existing hypertension
What is the name given to the fall in blood pressure over night?
The nocturnal dip
Explain the association between the nocturnal dip and risk of cardiovascular disease
The more significant the nocturnal dip, the more protected the patient is against cardiovascular disease.
What is a reversed nocturnal dip?
higher blood pressure at night compared to during the day
What could cause a reversed nocturnal dip?
nightshift work patterns or diabetics who have lost their normal autonomic blood pressure control
What is white coat hypertension?
Hypertension caused by stress associated with hospitals/medical staff
Is white coat hypertension linked to increased cardiovascular risk?
Yep
Describe “masked hypertension”
a normal blood pressure (BP) in the clinic but an elevated BP out of the clinic. There is no known cause
What is used to calculate a hypertensive patient’s risk of a cardiovascular event in the next 10 years?
The assign risk calculator (q-risk)
What is the BHS recommended blood pressure target?
<135/80mmHg
What is the q-risk score at which treatment for hypertension should be commenced?
10% / 10years
Explain the way in which antihypertensive drugs are dosed and why
Hypertension is treated using a stepped approach- low doses of several different drugs are used
This approach minimises adverse events and maximises patient compliance
Why are different types a=of antihypertensive drugs offered to old and young patients?
young patients tend to have high renin driven hypertension and elderly patients tend not to have high renin driven hypertension
What is the first line antihypertensive offered to young patients not of afro-carribean origin and not young women of childbearing age?
ACE inhibitors/ angiotensin receptor blockers
Why are ACE inhibitors/ angiotensin receptor blockers not offered to women of childbearing age?
They are fetotoxic
Why are ACE inhibitors/ angiotensin receptor blockers not offered to patients of afro-carribean origin?
They are at risk of angioedma
What is the first line antihypertensive drug that should be offered to Elderly (>55) individuals / individuals of Afro-Caribbean origin (any age)?
Calcium channel blockers and/or thiazide-type diuretics (start black people of Afro-Caribbean decent on the thiazide-type diuretic and Caucasians on the calcium channel blocker)
What is the blood pressure target in patients over the age of 80?
<145/85
When should a patient with stage 1 (>135/85 ambulatory BP) be offered antihypertensive treatment?
Offer treatment to patients aged under 80 years with an ambulatory blood pressure >135/85 with one or more of the following:
• target organ damage
• established cardiovascular disease
• renal disease
• diabetes
• a 10-year cardiovascular risk equivalent to 10% or greater.
Which stage 2 (>150/95mmHg) hypertension patients should be offered antihypertensives?
All of the
Describe the antihypertensive medications that should be given to a patient >55 years old, not of afro-carribean heritage
- Calcium channel blocker
- Thiazide type diuretic
- ACE inhibitor
- Beta blocker
Describe the antihypertensive medications that should be given to a patient <55 years old
- if <40 years old, seek specialist advice and investigate secondary causes
- if >40 years old, give;
- an ACE inhibitor
- thiazide like diuretic
- calcium channel blocker
- beta blocker
Describe the antihypertensive medications that should be given to an afrocarribean patient of any age >40
- thiazide like diuretic
- calcium channel blocker
- beta blocker
Describe the antihypertensive medications that should be given to a patient of childbearing age (not of afro-carribean decent)
- Calcium channel blocker/beta blocker
- Thiazide like diuretic
- Add whichever you didn’t give initially- either calcium channel blocker or beta blocker
What drugs should be given in resistant hypertension where the blood potassium level is higher than 4.5?
Higher dose thiazide like diuretics
What drugs should be given in resistant hypertension where the blood potassium level is less than 4.5?
Low dose spironolactone (be cautious in people with a reduced eGFR because they have an increased risk of hyperkalaemia)
What are the 4 most significant contraindications of ACE inhibitors?
- Renal artery stenosis (as this condition may precipitate renal failure or renal infarction)
- Impaired renal function (as it leaves the patient vulnerable to renal failure)
- Hyperkalaemia (ACE inhibitors will worsen hyperkalaemia)
- Fertile female (ACE inhibitors are teratogenic)
Describe the three most significant ACEi drug interactions and their consequences
- ACE inhibitors-NSAID interactions will precipitate acute renal failure
- ACE inhibitors- potassium supplements will cause hyperkalaemia
- NSAIDS- Potassium sparing diuretics will cause hyperkalaemia
Name 2 ACE inhibitor drugs
Ramipril, Perindopril
What is the benefit of using an Angiotensin II antagonist over an ACE inhibitor?
ACE inhibitors cause cough and AGII antagonists dont (there is no outcome benefit of either)
Name the 2 different types of calcium channel blocker
- Vasodilator
2. Cardiac (blocks the L-type channels in the heart)
Name 2 vasodilating calcium channel blockers
Amlodipine
Felodipine
name 2 cardiac L-type channel blocking CCBs
Verapamil/Diltiazem
Wht impact do calcium channel blockers have on the heart?
They reduce the heart rate
List 5 adverse effects of L-type calcium channel blockers
- Flushing
- Headache
- Ankle oedema
- Indigestion and reflux oesophagitis
- Bradycardia and constipation (rate limiting CCBs only)
List the three contraindications of calcium channel blockers
Acute myocardial infarction
Heart failure
bradycardia (for the rate limiting CCBs)
Explain how thiazide like diuretics work
These drugs act by causing the Urinary excretion of sodium ad dilating resistance vessels
How long does it take for the anti-hypertensive effect of thiazide like diuretics to become apparent?
Weeks
What are the adverse reactions associated with thiazide like diuretics?
Gout
Erectile dysfunction