I am a professional pharmacist. These slides provide for pharmacy department students. These slides describe pathology topic hypertension.

2. Hypertension
By
Khezar Hayat
Lecturer, IPA, UVAS

3. • High blood pressure, defined as a repeatedly elevated blood pressure
exceeding 140 over 90 mmHg -- a systolic pressure above 140 or a
diastolic pressure above 90.
Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High
Blood Pressure (JNC 7)
Hypertension

5. Overall, approximately 20% of the world’s adults are estimated to have
hypertension

6. • About 75 million American adults (29%) have high blood pressure—
that’s 1 of every 3 adults.
• High blood pressure costs the nation $46 billion each year. This total
includes the cost of health care services, medications to treat high
blood pressure, and missed days of work
Epidemiology

9. Classification of Hypertension

10. Hypertension
Primary
Hypertension
Secondary
Hypertension
Types of Hypertension

11. • Essential hypertension or idiopathic hypertension
• It is the most common type of hypertension, affecting 95% of
hypertensive patients
Primary Hypertension

12. • Inessential hypertension
• It is much less common than the other type, called essential
hypertension, affecting only 5% of hypertensive patients.
• It has many different causes including endocrine diseases, kidney
diseases, and tumors.
• It also can be a side effect of many medications.
Secondary Hypertension

13. Hypertension is rarely accompanied by symptoms, and its identification is
usually through screening, or when seeking healthcare for an unrelated
problem.
Some with high blood pressure report headaches (particularly at the back of
the head and in the morning), vertigo, tinnitus (buzzing or hissing in the ears),
altered vision or fainting episodes.
These symptoms, however, might be related to associated anxiety rather than
the high blood pressure itself.
Signs and symptoms

14. • In general the major causes of hypertension are the following:
• Hectic and stress filled life style
• Unhealthy food habits
• Obesity
• Excessive consumption of liquors
• Smoking
• Over consumption of tea/coffee
• Insufficient rest and sleep
• Metabolic disorders
Causes of Hypertension

15. • Excessive use of pain killers and other strong medicines
• Genetic disorders
• Over consumption of oily food and fast food
• High salt intake
• Emotional and Physical stress
• Family history of hypertension
Causes of Hypertension

16. These are the fundamental factors which determine the value of BP.
They are
1. Cardiac output (Describes the volume of blood being pumped by the
heart, in particular by the left or right ventricle, per unit time)
2. Peripheral vascular resistance
These are also called as factors controlling BP.
Pathophysiology of Hypertension
BP= Cardiac Output X PVR

18. It is subsequently converted to angiotensin II by the enzyme angiotensin-converting enzyme found in the
lungs.
Plasma renin then carries out the conversion of angiotensinogen released by the liver to angiotensin I.
When blood volume is low, juxtaglomerular cells in the kidneys activate their prorenin and secrete renin
directly into circulation.
The renin-angiotensin system (RAS) or the renin-angiotensin-aldosterone system (RAAS) is a hormone system
that regulates blood pressure and water (fluid) balance.
RAAS

19. If the renin-angiotensin-aldosterone system is abnormally active, blood pressure will be too high
This increases the volume of fluid (Cardiac Output) in the body, which also increases blood pressure.
Aldosterone causes the tubules of the kidneys to increase the reabsorption of sodium and water into the blood.
Angiotensin II also stimulates the secretion of the hormone aldosterone from the adrenal cortex.
Angiotensin II is a potent vaso-active peptide that causes blood vessels to constrict, resulting in increased blood pressure.
RAAS

20. RAAS

21. Agents That Blocks RAAS

23. • A high sodium intake may result in water retention.
• Some people are Na sensitive (about 20%) ; not everyone with high
salt diet develops hypertension
High Salt Intake and Hypertension

25. Mutations affect blood pressure by altering renal salt handling
Mutation in 10 genes which control the blood
pressure

26. • Obesity resulting in increased blood volume resulting in increased CO.
• As you gain weight, the amount of blood circulating through your
body increases. This puts added pressure on your artery walls,
increasing your blood pressure.
• Excess weight often is associated with an increase in heart rate and a
reduction in the capacity of your blood vessels to transport blood.
Obesity and Hypertension

28. • Stress and increased SNS activity
• Produces increased vasoconstriction
• ↑ HR
• ↑ Renin release
• Angiotensin II causes direct arteriolar constriction, promotes vascular
hypertrophy and induces aldosterone secretion
Stress Induced Hypertension

29. • Insulin resistance & hyperinsulinemia
• High insulin concentration stimulates SNS activity and impairs nitric
oxide–mediated vasodilation
• Not present in secondary hypertension and don’t improve when
hypertension is treated
Insulin Resistance and Hypertension

30. Nicotine in tobacco raises blood pressure by stimulating sympathetic neurons to
increase vasoconstriction and by stimulating the adrenal medulla to increase
secretion of epinephrine and norepinephrine.
Smoking and Hypertension

31. • The autonomic nervous system plays a central role in maintaining
cardiovascular homeostasis via pressure, volume, and chemoreceptor
signals.
• It does this by regulating the peripheral vasculature, and kidney
function, which in turn affect cardiac output, vascular resistance, and
fluid retention.
• Excess activity of the sympathetic nervous system increases blood
pressure and contributes to hypertension
Role Autonomic Nervous System in Hypertension

32. • It does this by regulating the;
• Peripheral vasculature, and kidney function,
which in turn affect
• Cardiac output, Vascular resistance, and Fluid retention.
Simple Mechanism
Sympathetic activity
Parasympathetic
activity
VASOCONSTRICTION VASODILATATION

33. Baroreceptors entered the medulla (tractus solitarius)
Secondary signals inhibit the vasoconstrictor center of medulla
and excite the vagal parasympathetic center
VASODILATATION OF THE
VEINS AND ARTERIOLES
(NO)
Therefore, excitation of baroreceptors by high pressure in the arteries
reflexly causes arterial pressure to decrease (as decrease in PR and CO)
DECREASED HEART RATE AND
STRENGTH OF HEART
CONTRACTION
EFFECT
NOTE : Conversely, low pressure has opposite effects, reflex causing the pressure rise
back to normal.

34. Short-term Regulation of Falling Blood Pressure
Baroreceptors inhibited
Decreased impulses to the brain
Decreased parasympathetic activity,
increased sympathetic activity
Effects
Heart
increased heart rate and
increased contractility
Vessels
increased vasoconstriction
Adrenal gland
release of epinephrine and
norepinephrine which enhance heart rate
Contractility and vasoconstriction
Increased blood pressure

35. • The mechanisms of increased sympathetic nervous system activity in
hypertension involve alterations in baroreflex and chemoreflex
pathways at both peripheral and central levels.
• Arterial baroreceptors are reset to a higher pressure in hypertensive
patients, and this peripheral resetting reverts to normal when arterial
pressure is normalized.
Baroreflex and Blood Pressure

36. • Furthermore, there is central resetting of the aortic baroreflex in
hypertensive patients, resulting in suppression of sympathetic
inhibition after activation of aortic baroreceptor nerves.
• This baroreflex resetting seems to be mediated, at least partly, by a
central action of angiotensin II.
Baroreflex and Blood Pressure

37. pO2 and pH

pCO2 
Stimulation of
vasomotor center
CO  HR vasoconstriction
BP (speeding return of blood
to the heart and lungs)
Chemorceptors and Blood Pressure

38. Endothelial Dysfunction
• The endothelium of blood vessels produces an extensive range of
substances that influence blood flow and, in turn, is affected by
changes in the blood and the pressure of blood flow.
• For example, local nitric oxide and endothelin, which are secreted by
the endothelium, are the major regulators of vascular tone and blood
pressure.
• In patients with essential hypertension, the balance between the
vasodilators and the vasoconstrictors is upset

39. Endothelial Dysfunction
• Evidence suggests that oxidant stress alters many functions of the
endothelium, including modulation of vasomotor tone.
• Inactivation of nitric oxide (NO) by superoxide and other reactive
oxygen species (ROS) seems to occur in conditions such as
hypertension.
• It has been suggested that angiotensin II enhances formation of the
oxidant superoxide at concentrations that affect blood pressure.

40. Sodium/Potassium ratio hypothesis of essential hypertension
• A 2007 review article states that while excessive sodium consumption
has long been recognized as contributing to the risk of hypertension,
"potassium, the main intracellular cation, has usually been viewed as
a minor factor in the pathogenesis of hypertension.
• However, abundant evidence indicates that a potassium deficit has a
critical role in hypertension.

41. Sodium/Potassium ratio hypothesis of essential hypertension
• The authors state that modern, western, high sodium, low potassium
diets result in corresponding changes in intracellular concentration of
these, the two most important cations in animal cells.
• This imbalance leads to contraction of vascular smooth muscle,
restricting blood flow and so driving up blood pressure.

42. Diabetes Complications (Diabetic Nephropathy)
• Diabetes can damage your kidneys' filtering system, which can lead to
high blood pressure.

43. Polycystic kidney disease
• In this inherited condition, cysts in your kidneys prevent the kidneys
from working normally and can raise blood pressure.

44. Glomerular disease
• Your kidneys filter waste and sodium using microscopic-sized filters
called glomeruli that can sometimes become swollen. If the swollen
glomeruli can't work normally, you may develop high blood pressure.

45. Renovascular hypertension
• . This type of hypertension is caused by narrowing (stenosis) of one or
both arteries leading to your kidneys.
• t's often caused by the same type of fatty plaques that can damage
your coronary arteries (atherosclerosis) or a separate condition in
which the muscle and fibrous tissues of the renal artery wall thicken
and harden into rings (fibromuscular dysplasia).
• Renovascular hypertension can cause irreversible kidney damage.

46. Cushing syndrome
• In this condition, corticosteroid medications may cause secondary
hypertension, or hypertension may be caused by a pituitary tumor or
other factors that cause the adrenal glands to produce too much of
the hormone cortisol.

47. Aldosteronism
• . In this condition, a tumor in the adrenal gland, increased growth of
normal cells in the adrenal gland or other factors cause the adrenal
glands to release an excessive amount of the hormone aldosterone.
• This makes your kidneys retain salt and water and lose too much
potassium, which raises blood pressure.

48. Pheochromocytoma
• This rare tumor, usually found in an adrenal gland, increases
production of the hormones adrenaline and noradrenaline, which can
lead to long-term high blood pressure or short-term spikes in blood
pressure.

49. Hyperparathyroidism
• The parathyroid glands regulate levels of calcium and phosphorus in
your body. If the glands secrete too much parathyroid hormone, the
amount of calcium in your blood rises — which triggers a rise in blood
pressure.

50. Sleep apnea
• In this condition, often marked by severe snoring, breathing
repeatedly stops and starts during sleep, causing you to not get
enough oxygen.
• Not getting enough oxygen may damage the lining of the blood vessel
walls, which may make your blood vessels less effective in regulating
your blood pressure.
• In addition, sleep apnea causes part of the nervous system to be
overactive and release certain chemicals that increase blood pressure.