1. Anatomy and Physiology
The Cardiovascular System

2. The cardiovascular system contains the heart, blood vessels (BVs), and blood.
Its function is to transport oxygen and nutrients throughout the body. It does this by circulating blood.
An average body contains ~5 liters of blood but the heart pumps ~7,000 liters of blood daily while the heart contracts ~2.5 billion times in an average lifetime.

3. The Heart: This is a powerful pump
It is found in the thoracic (chest) cavity behind the sternum and mediastinum
Average heart size is 14 X 9 cm
It is separated into chambers: 2 right and 2 left (or 2 upper and 2 lower)

4. It is covered by the pericardium (a membrane) which has 2 layers:
Visceral pericardium (covers the heart; inner layer); a.k.a. epicardium
Parietal pericardium (covers the visceral pericardium; outer layer)
The pericardial cavity is the space between these layers which contains serous fluid
Pericarditis is inflammation of the pericardium usually caused by viral or bacterial infection.

5. The Heart Walls This is composed of 3 layers:
Epicardium protects the heart (reduces friction); this contains connective tissue & adipose
Myocardium is the middle layer; contains mostly cardiac tissue
Endocardium is the innermost layer; contains epithelium & connective tissue and elastic & collagenous fibers
The Heart Walls

6. Heart Chambers and Valves:
There are 4 chambers:
The atria (sing. atrium) receive blood
The ventricles send blood (from the atria)
The right & left chambers are separated by a wall called the septum.
There are several valves in the heart that provide the main function of regulating blood flow in ONE direction only (prevents backflow).

7. The Heart Walls and Chambers:

8. Atrioventricular valves (a. k. a
Atrioventricular valves (a.k.a. A-V valves b/c they are between the atria and ventricles): there is 1 on the right & 1 on the left.
Tricuspid valve is between the right atrium and ventricle; blood flows from the right atrium to the right ventricle.
Bicuspid valve is between the left atrium and ventricle; blood flows from the left atrium to the left ventricle.
Pulmonary valve: at the base of the pulmonary trunk; this enables blood to leave the heart (and flow to the lungs thru the pulmonary arteries); blood flows out of the right ventricle
Aorta valve: at the base of the aorta (a large artery); blood flows out of the left ventricle
Heart Valves:

9. Heart Valves:

10. Pulmonary Circulation: (heart to lungs)
Pulmonary arteries: carry blood to lungs
Pulmonary veins: return blood from lungs to heart (left side)
Systemic Circulation: (heart to rest of body)
Aorta: main artery (largest) that pumps blood from heart to all body tissues (except lungs)
Superior & Inferior Vena Cava: bring blood back into heart from body tissues.

12. Blood Flow Path: begins with O2 poor blood:
Right Atrium Right Ventricle Pulmonary Trunk Pulmonary Arteries Alveoli of lungs for O2 Pulmonary Veins Left Atrium Left Ventricle Aortic Valve Aorta Body

14. The Cardiac Conduction System:
This coordinates the cardiac cycle
Contains the sinoatrial node (a.k.a. S-A node) located beneath the epicardium:
This acts as the pacemaker of the heart b/c it is rhythmic (meaning it starts impulses, thereby generating the heart’s rhythm).
Contains the atrioventricular node (a.k.a. A-V node) located beneath the endocardium
This acts as the impulse conduction pathway between the atria and ventricles
The Cardiac Conduction System:

15. Cardiac Cycle & Sounds:
The cardiac cycle is 1 heart contraction AND 1 heart relaxation, or a complete heartbeat.
Atrial systole is atrial contraction while atrial diastole is atrial relaxation.
When listening to the heartbeat with a stethoscope, it sounds like lubb-dupp. The lubb is ventricular contraction while the dupp is ventricular relaxation.

16. A murmur is a sound that is heard when there is slight damage to a valve of the heart.
The damage is the leaking of blood through a valve b/c the valve does not completely close.

17. Heart problems can be detected with the use of an ECG.
An electrocardiogram (a.k.a. ECG) is a recording of electrical charges in the myocardium during a cardiac cycle.
Heart problems can be detected with the use of an ECG.

18. The heart rate can change(temporarily) by certain factors:
Heart Regulation:
The heart rate can change(temporarily) by certain factors:
Neural (ANS) controls: stress
Hormones & ions: changes or imbalances in electrolytes (Ca++, Na+, K+), thyroxine, or epinephrine
Physical factors: temperature, age, gender

19. Blood Vessels (BVs):
These include the arteries, arterioles, capillaries, venules and veins.
The arteries take blood away from the heart; vasoconstriction & vasodilation (opening & closing of an artery) controls blood flow and blood pressure.
Oxygenated Blood (red)

20. Arteries (& Veins) have 3 layers:
Tunica intima is the innermost layer containing endothelium (internal epithelium) which helps prevent blood clotting
Tunica media is the middle layer
Tunica externa is the outermost layer
The arterioles come from the arteries (they are smaller arteries)

21. Found between arteries and venules
Capillaries are the smallest BVs
Found between arteries and venules
Gases & nutrients are exchanged thru their membranes (semipermeable)
This occurs by diffusion, filtration & osmosis
The amount of capillaries found within a tissue varies according to the tissue’s O2 requirement (more O2 required=more capillaries)

23. Venules are small veins
Veins carry blood to the heart from the body; these run parallel to arteries.
Veins have 3 layers (like arteries) but not as distinct
Thinner walls than arteries
Less elastic but greater diameter than arteries
Many contain valves which act as flaps preventing backflow of blood

25. Varicose Veins: http://www.brvsa.com/images/varicose2.jpg

26. Physiology of Circulation:
Vital Signs: Arterial pulse, blood pressure, rate of respiration, and body temperature.
Pulse: each beat of the left ventricle as it travels through the arterial system.
Physiology of Circulation:

27. This is the contraction and relaxation of an arterial wall.
A pulse is felt at certain points on the body. This is due to an artery close to the surface of the skin.
This is the contraction and relaxation of an arterial wall.

28. Blood Pressure:
Blood pressure can be defined as the force of blood against BVs.
When the ventricles contract with the maximum pressure is the systolic pressure.
When the ventricles relax with the lowest pressure is the diastolic pressure.

29. Factors that Influence Blood Pressure:
Heart action: this determines the total volume of blood entering the arterial system.
Blood volume: this is ~5 liters or 8% of body weight. This equals the sum of the elements and plasma.
Blood volume is proportional to bp (normally). When blood volume decreases, bp drops; dehydration will also influence bp b/c it affects blood volume.
Factors that Influence Blood Pressure:

30. Thicker blood (meaning it has more parts) creates higher bp.
Factors that Influence Blood Pressure:
Peripheral Resistance: this is the force of the friction between blood and blood vessels. This can hinder blood flow.
Blood viscosity: this is the ease with which blood particles move past each other. Greater viscosity=greater resistance.
Thicker blood (meaning it has more parts) creates higher bp.

31. Factors that Influence Blood Pressure:
Additional Factors that may influence blood pressure:
ANS
Renal Factors (kidneys)
Temperature
Hormones
Diet
Factors that Influence Blood Pressure:

32. Look up in text or online!
Know the following:
endocarditis, angina, infarct, ischemia, fibrillation, tachycardia, bradycardia, congestive heart failure, pulmonary edema, varicose veins, thrombophlebitis, hypotension, hypertension, atherosclerosis, and coronary artery disease

33. THE END!

34. This slide show was developed by Dana Halloran,
Cardinal Mooney High School, Sarasota, FL.
Used with her personal permission,
adapted and amended by Rosa Whiting,
Manatee School for the Arts, Palmetto, FL.