3. Introduction
Definition. Hypertension or high blood pressure is a condition in which the
blood pressure in the arteries is chronically elevated.
Systolic blood pressure (SBP) of >140 mmHg or diastolic blood pressure (DBP)
of >90 mmHg.
Blood pressure is the force of blood that is pushing up against the walls of the
blood vessels.
Blood pressure is summarized by 2 measurements. Systolic and Diastolic
1. Systolic – is the amount of pressure in your arteries during the contraction of the
heart muscle.
2. Diastolic – is the amount of pressure in the arteries when the heart rest between
beats. This is the time when the heart fills with blood and gets oxygen.
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4. Introduction cont.
If the pressure is too high, the heart has to work harder to pump and this
could lead to organ damage and several illnesses such as heart attack, stroke,
heart failure, aneurysm or renal failure.
Pulse pressure
Is the different between systolic and diastolic blood pressure.
This is frequently high in older people with Hypertension. This means that SBP
pressure may be abnormally high but DBP may be normal or low. This
condition is called Isolated systolic hypertension. There is arterial stiffness
which typically accompanies ageing and is exacerbated by HBP.
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5. Etiology
Hypertension maybe Primary (essential), which may develop as a result of
environmental or genetic causes or secondary hypertension, which has multiple
etiologies.
1.Primary (Essential) hypertension.
This means hypertension with no obvious underlying medical cause and it caters
for 90 – 95% of all the cases.
Risk factors
Genetics
Race
Age
Smoking
Stress
Obesity
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6. Etiology cont.
Lack of exercise
High levels of salt intake
Insufficient levels of calcium, potassium and magnesium in the body
Excessive consumption of Alcohol
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7. Etiology cont.
2.Secondary Hypertension
This means hypertension is caused by other medical condition that affects the
kidney, arteries, heart, or endocrine system. This type of hypertension caters
for 5 – 10% of all the cases.
Risk factors
Kidney disease (renal vascular disease)
Endocrine problems (Diabetes, Adrenal and thyroid problems or tumors)
CVS conditions e.g. coarctation
Drugs ( corticosteroids, birth control pills, cocaine…etc)
Pregnancy
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8. Signs, symptoms and diagnosis
There is no guarantee that a person with hypertension will present any symptoms
of the condition. About 33% per cent of people actually do not know that they
have high blood pressure and this ignorance can last for years. For this reason, it
is advisable to undergo periodic blood pressure screening even when no
symptoms are present.
Extremely high blood pressure may lead to some symptoms, however and these
include:
Severe headache
Fatigue
Dizziness
Nausea
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9. Signs, symptoms and diagnosis cont.
Problems with vision
Chest pain
Breathing problems
Irregular heartbeat
Blood in the urine
Fainting episodes
Hypertension may be diagnosed by a health professional who measures blood
pressure by using a devise called Sphygmomanometer.
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10. Signs, symptoms and diagnosis cont.
Investigations
Urinalysis for
Blood
Protein
Glucose
Plasma creatinine and cholesterol
ECG to detect left ventricular hypertrophy or evidence of coronary artery disease
Chest radiography for cardiomegaly, heart failure, coarctation of aorta (in selected
patients).
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12. Treatment
Pts with mild hypertension without other cardiac risk factors should be
treated non pharmacologically.
Pts with major risk factors such as DM or heart failure should be treated with
antihypertensives even when the BP is in prehypertension stage.
1.Non Pharmacological
Weight loss (SBP 5-20mmHg)
Limit alcohol intake to no more than 1 oz (30mL) of ethanol per day for men or
0.5oz (15mL) for women or people with lighter weight.( SBP 2-4mmHg)
Reduce sodium intake to no more than 100 mmol/day (2.4 g sodium or 6g sodium
chloride; range of approximate SBP 2-8 mmHg)
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13. Treatment cont.
Maintain adequate intake of dietary potassium (approximately 90 mmol/day.
Maintain adequate intake of dietary calcium and magnesium for general health.
Stop smoking and reduce intake of dietary saturated fat and cholesterol for overall
cardiovascular health.
Engage in aerobic exercise at least 30 minutes daily for most days (range of
approximate SBP reduction, 4-9 mmHg)
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14. Treatment cont.
2.Pharmacological
Drug classes
1. Angiotensin-converting enzyme inhibitors ACEs
2. Angiotensin II receptor antagonists ARBs
3. Adrenergic receptor antagonists
i. Alpha blocker
ii. Beta blocker
4. Calcium channel blockers CCBs
5. Diuretics
i. Loop diuretics
ii. Thiazide diuretics
iii. Potassium-sparing diuretics
6. Vasodilators
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15. Treatment cont.
1.Angiotensin-converting Enzymes inhibitors ACEs
These inhibit the activity of angiotensin-converting enzyme, an enzyme responsible for the
conversion of angiotensin I into angiotensin II, a potent vasoconstrictor.
ACE inhibitors produce vasodilation by inhibiting the formation of angiotensin II
ACE also breaks down bradykinin ( a vasodilator substance).
ACE dilates arteries and veins, promotes renal excretion of sodium and water and inhibit cardiac
and vascular remodeling.
Therapeutic uses
• Hypertension.
• Heart failure.
• Post-myocardial infarction.
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17. Treatment cont.
ACEs are contraindicated in patients with;
Pregnancy .
Previous angioedema associated with ARBs/ACEs therapy.
Hypersensitivity to ARBs/ACEs.
Examples
• Captopril tab. 12.5 – 50 mg twice daily
• Enalapril tab. 5 – 40 mg daily once / twice.
• Lisinopril tab. 5 – 40 mg once daily.
• Fosinopril tab. 10 – 40 mg once daily
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18. Treatment cont.
2. Angiotensin II Receptor antagonists/Sartans ARBs
These drugs have very similar effects to ACEs and are used for the same
indications (Hypertension, heart, failure, post-myocardial infarction).
Their mechanism of action, however, is very different from ACE inhibitors, which
inhibit the formation of angiotensin II (AT1).
Therapeutic uses
• Hypertension
• Heart failure
• Post-myocardial infarction
Side effects of ARBs
Dizziness
Headache
Hyperkalemia
Angioedema
Cough
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19. Treatment
Examples
• Telmisartan tab 40 – 80 mg once daily.
• Losartan 50-500mg twice daily.
• Candesartan 8-32mg once daily
• Olmesartan 20 – 40 mg once daily
3. Adrenergic receptor antagonist
These are drugs that inhibits the function of adrenergic receptor.
There are five Adrenergic receptors, which are divided into two groups, Alpha
blockers and beta blockers.
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20. Treatment
a. Alpha blockers
Alpha blockers cause blood vessels to dilate, thereby lowering blood pressure.
Alpha blockers are also used to treat Prostate enlargement in men.
Examples
• Methyldopa tab 250 – 500mg daily in two or three divided doses.
Note: Methyldopa is the effective drug to use when treating pregnancy
induced hypertension.
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21. Treatment cont.
b. Beta blockers
Beta blockers bind to beta-adrenoceptors located in cardia nodal tissue, the
conducting system and contracting myocytes.
Side effects
Bronchoconstriction can occur. Therefore non-selective beta blockers are contra-
indicated in patients with asthma and or chronic obstructive pulmonary diseases.
Cold extremities.
Bradycardia.
Hypotension.
Worsening of heart failure.
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22. Treatment cont.
Examples
• Atenolol tab. 25 – 100mg daily once/in divided doses.
• Propranolol tab. 40 -320 mg daily once /in divided doses.
• Metoprolol tab. 50 – 100 mg once /in divided doses
4. Calcium channel blockers CCBs
CCBs bind to L-type calcium channels located on cardiac myocytes and
cardiac nodal tissue (sinoatrial and atrioventricular nodes). These channels
are responsible for regulating the influx of calcium into cardiomyocytes,
which in turn stimulates cardiac myocyte contraction.
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24. Treatment cont.
5. Diuretics
Diuretics drugs increases urine output by the kidney (i.e., promote diuresis).
This is accomplished by altering how the kidneys handles sodium. If the
kidney excretes more sodium, then water excretion will also increase.
Most diuretics produce diuresis by inhibiting the reabsorption of sodium at
different segments of the renal tubular system.
There are 3 common types of diuretics and these are;
a. Loop diuretic
b. Thiazide diuretic
c. Potassium-sparing diuretic
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25. Treatment cont.
a. Loop diuretics
These are the most powerful diuretics.
The inhibit the sodium-potassium-chloride cotransporter in the thick ascending
limb. This transporter normally reabsorbs about 25% of the load; therefore
inhibition of this pump can lead to a significant increase in the distal tubular
concentration of sodium, reduced hypertonicity of the surrounding interstitium
and less water reabsorption in the collecting duct.
Side effects
Hypokalemia
Dehydration
Anemia
Diarrhea
Anorexia
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26. Treatment cont.
Drug interaction with Loop diuretics
• NSAID-reduce diuretic efficacy.
• Corticosteroids – enhance hypokalemia
• Aminoglycosides-enhance ototoxicity, nephrotoxicity.
Example of loop diuretics
Furosemide 20 – 80 daily in divided doses
b. Thiazide diuretic
These are most commonly used diuretics, they inhibit the sodium-chloride
transporter in the distal tubule. Because this transporter only reabsorb about 5%
of filtered sodium, these diuretics are less efficacious than loop diureticsin
producing diuresis natriuresis.
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27. Treatment cont.
Side effects of Thiazides
• Hypokalemia
• Dehydration
• Hyperglycemia in diabetes
• Hypotension
Drug interaction with Thiazides
• NSAID- reduce efficacy
• Beta blockers – potentiates hyperglycemia, hyperlipidemia
• Corticosteroids – enhance hypokalemia
Example of Thiazides
• Hydrochlorothiazide 25mg daily once
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28. Treatment cont.
c. Potassium-sparing diuretics
unlike loop and thiazide diuretics, some of these drugs do not act directly on
sodium transport. Some of these drugs in this class antagonize the action of
aldosterone (aldosterone receptor antagonists) at the distal segment of the
distal tubule.
This cause more sodium and water to pass into the collecting duct and be
excreted in the urine.
They are called potassium-sparing diuretics because they do not produce
hypokalemia like loops and thiazides diuretics.
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30. Treatment cont.
6. Vasodilators
As the name implies, vasodilators drugs relax the smooth muscles in the blood
vessels, which causes the vessels to dilate.
Dilation of arterial (resistance) vessels leads to a reduction in systemic vascular
resistance, which leads to fall in arterial blood pressure.
Example of vasodilators
• Hydralazine 10 - 50mg daily q.i.d (i.v/i.m 20-40mg repeat as necessary)
Side effects
• Headache
• Palpitation
• Conjunctivitis
• Hypotension
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31. Treatment Guidelines.
First drug Second drug Comment
Effective combination
ACEs or ARBs plus Calcium channel blocker Diabetes, lipid abnormalities
ACEs or ARBs plus Thiazides diuretics Heart failure, post stroke
ACEs or ARBs plus Beta-blockers Post myocardial infarction, heart failure
Beta-blocker plus Dihydropyridine Calcium Channel Blocker Coronary heart disease
Thiazide diuretics Calcium channel blocker
Thiazide diuretics Beta-blockers Not recommended in diabetes, glucose intolerance,
metabolic syndrome.
Combination to use with care
Diltiazem plus Beta-blockers Due to risk of heart block, risk is less with verapamil
ACEs plus Potassium-sparing diuretics Due to risk of hyperkalemia
Combination to avoid
ACEs plus ARBs Increased risk of renal dysfunction
Verapamil Beta-blocker Due to risk of heart block
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32. Treatment Guideline cont.
Drug treatment strategy to reach blood pressure target
1 Starting drug treatment
Start with low-moderate recommended dose of first-line drug. If not well tolerated, change
to a different drug class, again start with low-moderate recommended dose.
2 If target not reached after 3 months.
Add a second drug from a different pharmacological class at a low-moderate dose, rather
than increasing the dose of the first drug. This maximizes antihypertensive efficacy, while
minimizing adverse effects.
3 If target not reached after 3 months.
If both antihypertensives drugs have been well tolerated, increase the dose of one drug
(excluding thiazide diuretic) incrementally to the maximal recommended dose before
increasing the dose of the other drug.
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33. Treatment Guideline cont.
4 If target not reached after 3 months.
If, despite maximal dose of at least 2 drugs, a third drug class may be started at a low-
moderate dose. It is advisable to reassess for non-adherence, secondary hypertension
and hypertensive effects of other drugs, treatment resistant state due to sleep apnea,
undisclosed use of alcohol or recreational drugs or high salt intake.
5 If blood pressure remain elevated, consider seeking specialist advice.
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