1. The Cardiovascular System The Heart and Circulation
Pages
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2. The Cardiovascular System
Includes the heart and the blood vessels
Functions:
Deliver oxygen/nutrients to cells/tissues
Remove carbon dioxide/waste products
Blood is the transport vehicle
© 2015 Pearson Education, Inc.

3. The Heart Location Orientation About the size of a human fist
Thoracic cavity
between the lungs within the inferior mediastinum (the central chamber of the thorax)
Orientation
Pointed apex directed toward left hip
Base points toward right shoulder
About the size of a human fist
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4. Figure 11.1a Location of the heart within the thorax.
Superior
vena cava
Aorta
Pulmonary
trunk
Left lung
Pericardium
(cut)
Apex of
heart
Diaphragm
(a)

5. Figure 11.1b Location of the heart within the thorax.
Midsternal line
2nd rib
Sternum
Diaphragm
(b)

6. Coverings of the Heart The heart is enclosed by the pericardium
Pericardium—a double-walled (2 layered) sac
Fibrous pericardium is loose and superficial
Serous membrane is deep to the fibrous pericardium and composed of two layers:
Parietal pericardium: outside layer that lines the inner surface of the fibrous pericardium
Visceral pericardium: lies directly on heart; also known as the epicardium
Serous fluid fills the space between the layers of pericardium
lubricates; prevents friction from the beating heart
© 2015 Pearson Education, Inc.

7. Figure 11.2 Heart wall and coverings.
Pulmonary
trunk
Fibrous pericardium
Parietal layer of
serous pericardium
Pericardium
Pericardial cavity
Myocardium
Epicardium
(visceral layer
of serous
pericardium)
Heart
wall
Myocardium
Endocardium
Heart chamber

8. Walls of the Heart Three layers comprise the walls of the heart:
Epicardium
Most superficial; connective tissue
(This is the visceral pericardium)
Myocardium
Middle layer- the one that contracts
Mostly cardiac muscle
Desmosomes hold cells together
gap junctions allow electrical wave to flow cell to cell
Endocardium
Inner layer known as endothelium
Endothelial cells are a layer of thin squamous cells with vascularity
A specialized type of epithelial cell
© 2015 Pearson Education, Inc.

9. Figure 11.2 Heart wall and coverings.
Pulmonary
trunk
Fibrous pericardium
Parietal layer of
serous pericardium
Pericardium
Pericardial cavity
Myocardium
Epicardium
(visceral layer
of serous
pericardium)
Heart
wall
Myocardium
Endocardium
Heart chamber

10. Chambers of the Heart Right and left side are separate pumps
Four chambers:
Atria -right and left (on top)
Receiving chambers
Ventricles -right and left (on bottom)
Discharging chambers
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11. Figure 11.3b Gross anatomy of the heart.
Left atrium
Right atrium
Left ventricle
Right ventricle
(b) Frontal section showing interior chambers and valves.

12. Dividing structures of the heart
Interventricular septum
Separates the two ventricles
Interatrial septum
Separates the two atria
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13. Figure 11.3b Gross anatomy of the heart.
Superior vena cava
Aorta
Left pulmonary artery
Right pulmonary
artery
Left atrium
Right atrium
Left pulmonary veins
Right pulmonary
veins
Pulmonary semilunar
valve
Left atrioventricular
valve (bicuspid valve)
Fossa ovalis
Aortic semilunar valve
Right atrioventricular
valve (tricuspid valve)
Left ventricle
Right ventricle
Chordae tendineae
Interventricular septum
Inferior vena cava
Myocardium
Visceral pericardium
(epicardium)
(b) Frontal section showing interior chambers and valves.

14. Heart showing Atrial Septal Defect

15. Hypertrophic Cardiomyopathy (HCM)

16. Pulmonary Circulation
Oxygen-poor blood flows from the right side of the heart to the lungs
Oxygen-rich blood returns to the left side of the heart from the lungs
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17. Systemic Circulation
Oxygen-rich blood flows from the left side of the heart (via the aorta) to body tissues
(oxygen is used at the cellular level; carbon dioxide is returned to circulation via veins for elimination from the body)
Oxygen-poor blood returns to the right side of the heart via the superior vena cava
© 2015 Pearson Education, Inc.

18. Figure 11.4 The systemic and pulmonary circulations.
Capillary beds
of lungs where
gas exchange
occurs
Pulmonary Circuit
Pulmonary
arteries
Pulmonary veins
Aorta and branches
Venae cavae
Left
atrium
Right
atrium
Left
ventricle
Right
ventricle
Heart
Systemic Circuit
Capillary beds
of all body tissues
where gas exchange
occurs
KEY:
Oxygen-rich, CO2-poor blood
Oxygen-poor, CO2-rich blood

19. Heart Valves Four valves:
Atrioventricular (AV) valves—between atria and ventricles
Bicuspid (mitral) valve (left side of heart)
Tricuspid valve (right side of heart)
Semilunar valves—between ventricle and artery
Pulmonary semilunar valve
Aortic semilunar valve
© 2015 Pearson Education, Inc.

21. Function of Heart Valves
Allow for unidirectional flow; prevent backflow
Open/close in response to pressure changes in heart
Leaky valves are ok… to a degree
Valves that cannot close correctly cannot prevent backflow
Valves that are damaged (due to infection) require more forceful contraction
This leads to a weak heart and potential heart failure

22. Animations showing blood flow
This link shows a summary of the process of blood flow:
ew0/chapter22/animation__the_cardiac_cycle__quiz_2_.html
This link shows a step by step process of flow:
ations/content/humanheart.html
This link shows a valve replacement!! Very cool
sIdppyaPQ

23. Blood supply to the HEART
The heart has its own circulatory system
Coronary arteries—branch from the aorta to supply the heart muscle with oxygenated blood
Cardiac veins—drain the myocardium of blood and dump into the Coronary sinus (located posterior and inferior)
From the sinus, blood empties into the right atrium and is returned to pulmonary circulation for re-oxygenation at the lungs
© 2015 Pearson Education, Inc.

24. Figure 11.3a Gross anatomy of the heart.
Superior vena cava
Aortic arch
Right pulmonary artery
Left pulmonary artery
Pulmonary trunk
Left pulmonary veins
Right pulmonary
veins
Left atrium
Right atrium
Right coronary artery
Left coronary artery
Anterior cardiac vein
Left ventricle
Right ventricle
Great cardiac vein
Small cardiac vein
Inferior vena cava
Apex