4-cardiovascular Pharmacy.pptx

1. Cardiovascular Physiology
Dr. Sahar Greish
Professor of physiology

2. Components of CV System
• Heart
• Vascular System
– Arteries
– Arterioles
– Capillaries
– Venules
– Veins

3. Heart
- Structure of the
heart:
• Atria
• Ventricles
• Valves
- Circulation of
blood in the
heart

4. Heart
Functions of the
components of the
heart:
• Atria: receive blood,
pump to the ventricles
• Ventricles: pump to
the organs
• Valves: allow
unidirectional flow

5. The atrioventricular (AV) valves:
– located between the atrium and ventricle in each
half of the heart
– permit blood to flow from atrium to ventricle but
not from ventricle to atrium.
– The right AV valve is called the tricuspid valve,
– The left AV valve is called the mitral valve.
Anatomical Overview

6. The opening of the right ventricle into the pulmonary
trunk and of the left ventricle into the aorta also contain
valves, the pulmonary and aortic valves, respectively.
The pulmonary and the aortic valves are called
Semilunar valves.
Function: These valves permit blood to flow into the
arteries during ventricular contraction but prevent blood
from moving in the opposite direction during ventricular
relaxation.
Anatomical Overview

7. The 2 Circuits of the CV System
The cardiovascular system
forms a circle,
There are actually two
circuits, both originating
and terminating in the
heart.
Two sets of blood circulation
• Systemic
• Pulmonary

8. Systemic Circulation
starts from left ventricle
ends in right atrium
transports oxygenated
blood to all organs &
transports non-
oxygenated blood back
to the heart
is a high-pressure
circulation

9. Pulmonary Circulation
starts from right
ventricle
ends in left atrium
transports non-
oxygenated blood to
the lungs & transports
oxygenated blood back
to the heart
is a low-pressure
circulation

10. • Thus the right side of the heart carries de-
oxygenated blood.
• The left side of the heart carries oxygenated
blood.
• The pulmonary veins carry oxygenated blood
from the lung to the heart.
• The pulmonary artery carries deoxygenated
blood from the heart to the lungs.
The Heart as A Pump

11. Cardiac Cycle
• Atrial systole ventricular systole diastole.
• The parts of the heart normally beat in orderly
sequence: Contraction of the atria (atrial
systole)  is followed by contraction of the
ventricles (ventricular systole)  and during
diastole all four chambers are relaxed.

12. Atrial and ventricular events of cardiac cycle
Cardiac Cycle

13. Conduction System of the Heart
• The heartbeat originates in a specialized cardiac
conduction system and spreads via this system to
all parts of the myocardium.
• The structures that make up the conduction
system are the:
1. sinoatrial node (SA node),
2. internodal atrial pathways,
3. atrioventricular node (AV node),
4. bundle of His and its branches, and
5. Purkinje system.

14. Origin & Spread of cardiac
excitation:

15. SA node is the normal pace maker of the
heart

16. Sequence of cardiac excitation

17. Extrinsic Innervation of the Heart
• Heart is stimulated
by the
sympathetic
cardioacceleratory
center
• Heart is inhibited
by the
parasympathetic
cardioinhibitory
center

18. Blood Supply to cardiac muscle
• The blood being pumped through the heart chambers does
not exchange nutrients and metabolic end products with the
myocardial cells.
• They, like the cells of all other organs, receive their blood
supply via arteries that branch from the aorta.
• The arteries supplying the myocardium are the coronary
arteries, and the blood flowing through them is termed
the coronary blood flow.
• The coronary arteries exit from the very first part of the
aorta and lead to a branching network of small arteries,
arterioles, capillaries, venules, and veins similar to those
in other organs.

19. Coronary Circulation: Arterial Supply

20. Coronary Circulation: Venous Supply

21. Arterial Blood Pressure

22. Definitions and normal values
Arterial blood pressure is defined as the lateral pressure
exerted by the column of blood on wall of arteries.
Arterial blood pressure is expressed in four different
terms:
1. Systolic blood pressure
2. Diastolic blood pressure
3. Pulse pressure
4. Mean arterial blood pressure.

23. Systolic blood pressure
Systolic blood pressure (systolic pressure) is defined as the
maximum pressure exerted in the arteries during systole of
heart.
Normal systolic pressure: 120 mm Hg (100 mm Hg to 140 mm
Hg).
Diastolic blood pressure
Diastolic blood pressure (diastolic pressure) is defined as the
minimum pressure exerted in the arteries during diastole of
heart.
Normal diastolic pressure: 80 mm Hg (60 mm Hg to 90 mm
Hg).
Definitions and normal values

24. Pulse pressure
Pulse pressure is the difference between the systolic
pressure and diastolic pressure.
Normal pulse pressure: 40 mm Hg (120 – 80 = 40).
Mean arterial blood pressure
Mean arterial blood pressure is the average pressure
existing in the arteries. Normal mean arterial
pressure: 93 mm Hg (80 + 13 = 93).
Mean arterial blood pressure = Diastolic pressure +
1/3 of pulse pressure
Definitions and normal values

25. Factors determining arterial blood
pressure

26. REGULATION OF ARTERIAL BLOOD
PRESSURE

27. 2-renin-angiotensin
mechanism

28. Hypertension

29. Hypertension
• Hypertension that is a result of (secondary to)
known disease processes is logically called
secondary hypertension (10%).
• Hypertension that is the result of complex
and poorly understood processes is not so
logically called primary, or essential,
hypertension (90%).

30. Essential Hypertension
• The vast majority of people with hypertension have
essential hypertension.
• An increased total peripheral resistance is a universal
characteristic of this condition.
• Cardiac rate and the cardiac output are elevated in
many, but not all, of these cases.
• The secretion of renin, which is correlated with
angiotensin II production and aldosterone secretion, is
likewise variable.
• Sustained high stress (acting via the sympathetic
nervous system) and high salt intake appear to act
synergistically in the development of hypertension.

31. Secondary hypertension
•Renovascular hypertension: This type of high blood pressure is
caused by narrowing (stenosis) of one or both arteries leading to the
kidneys.
•Pregnancy: (pregnancy-induced hypertension or preeclampsia).
•Medications and supplements: Various prescription medications
— such as pain relievers, birth control pills, and cortisol can cause high
blood pressure.
Some herbal supplements, including ginseng, and licorice have the same
effect.
•Cushing syndrome: In this condition, the adrenal glands produce too
much of cortisol hormone.
•Aldosteronism: The adrenal glands produce too much of the hormone
aldosterone. This makes salt and water retention.
•Thyroid problems: When the thyroid gland produces too much
thyroid hormone (hyperthyroidism).

32. Treatment of Hypertension
• lifestyle modifications: walking, cessation of
smoking, weight reduction, and a reduction in
sodium intake.
• If lifestyle modifications are insufficient, various
drugs may be prescribed.
• Most commonly,
– Diuretics that increase urine volume, thus decreasing
blood volume and pressure.
– β1-adrenergic receptor blockers (such as atenolol)
lower blood pressure by decreasing the cardiac rate
– ACE inhibitors, and various vasodilators may also be
used in particular situations.