The Cardiovascular System

1
The Cardiovascular System

• Chapter 14

2
Introduction

• Cardiovascular system heart, blood and blood
  vessels
• Cardiac muscle
• Makes up bulk of heart
• Provides force to pump blood
• Function transports blood

3
The Anatomy of the Heart
4
Introduction

• Located in the mediastinum
• Surrounded by pericardial sac
• Fibrous pericardium outer layer
• Serous pericardium inner layer

5
The Layers of the Heart Wall

• Epicardium outermost layer
• Pericardial cavity separates epicardium and
  serous pericardium
• Myocardium middle muscular layer
• Endocardium lines the heart

6
The Layers of the Heart Wall (contd.)
7
The Chambers of the Heart

• Upper chambers right and left atria
• Lower chambers right and left ventricles
• Chambers separated internally by septum
• External separations
• Coronary sulcus separates atria and ventricles
• Interventricular sulci separate ventricles

8
The Chambers of the Heart (contd.)
9
The Great Vessels of the Heart

• Superior vena cava
• Receives blood from upper body
• Inferior vena cava
• Receives blood from lower body
• Coronary sinus drains blood from heart

10
The Great Vessels of the Heart (contd.)

• Pulmonary trunk right and left artery
• Carries deoxygenated blood to lungs
• Pulmonary veins (four) return oxygenated blood
  to heart
• Ascending aorta oxygenated blood out to body
• Aortic arch, descending thoracic, abdominal

11
Four Chambers of the Heart and Great Vessels
12
The Valves of the Heart

• Atrioventricular
• Tricuspid (three cusps)
• Between right atrium and right ventricle
• Bicuspid (two cusps)
• Between left atrium and right ventricle
• Cusps attach to ventricles by chordae tendineae

13
The Valves of the Heart (contd.)

• Semilunar
• Pulmonary
• Right ventricle
• Pulmonary trunk exits the heart
• Aortic
• Left ventricle
• Ascending aorta leaves the heart

14
Blood Flow Through the Heart
15
Blood Flow Through the Heart (contd.)

• Two atria contract while ventricles relax
• Two ventricles contract while atria relax
• Deoxygenated blood returns from body to right
  atrium
• Sent to right ventricle, which pumps blood to
  lungs

16
Blood Flow Through the Heart (contd.)

• Oxygenated blood returns to left atrium
• Sent to left ventricle
• Left ventricle sends blood to the body via the
  ascending aorta

17
The Conduction System of the Heart
18
The Conduction System of the Heart (contd.)

• Sinoatrial (SA) node pacemaker initiates
  impulse ?
• Atrioventricular (AV) node sends impulse to AV
  bundle?
• Bundle of His sends impulses to both sides of
  system?

19
The Conduction System of the Heart (contd.)

• Purkinjes fibers send impulse to myocardial
  cells

20
The Conduction System of the Heart (contd.)
21
Animation The Heart

• See the conduction system at work in the 3-D
  Heart animation.

Click Here to Play Conduction System Animation
22
A Cardiac Cycle
23
A Cardiac Cycle (contd.)

• One cycle
• Atria contract / ventricles relax
• Ventricles contract / atria relax
• Systole contraction phase
• Diastole relaxation phase

24
Some Major Blood Circulatory Routes
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Some Major Blood Circulatory Routes (contd.)

• Systemic circulation
• All blood leaving left ventricle (oxygenated)
• All blood returning to right atrium
  (deoxygenated)
• Subdivisions
• Coronary circulation
• Hepatic portal circulation

26
Some Major Blood Circulatory Routes (contd.)

• Pulmonary blood flow to lungs for gas exchange
• Cerebral route to the brain
• Fetal between developing fetus and mother

27
Anatomy of Blood Vessels
28
Anatomy of Blood Vessels (contd.)

• Arteries and veins have three layers
• Tunica intima innermost layers
• Tunica media middle layer
• Tunica adventitia outer layer
• Lumen blood vessel cavity
• Anastomosis junction of blood vessels

29
Anatomy of Blood Vessels (contd.)

• Arteries thicker and stronger than veins
• Arterioles small arteries attach to capillaries
• Capillaries gas nutrient and waste exchange

30
Anatomy of Blood Vessels (contd.)

• Venules connect capillaries to veins
• Veins less elastic than arteries, contain valves

31
Major Arteries and Veins of the Body
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Ascending Aorta Branches

• Right and left coronary arteries branch off and
  supply the heart

33
Aortic Arch Branches

• 1st branch brachiocephalic artery
• Right common carotid artery and right subclavian
  artery
• 2nd branch left common carotid artery
• Left internal carotid artery and left external
  carotid artery

34
Aortic Arch Branches

• 3rd branch left subclavian artery
• Vertebral artery, axillary artery, brachial
  artery and radial and ulnar arteries

35
Thoracic Aorta Branches

• 10 pairs of intercostal arteries
• Bronchial arteries
• Esophageal arteries
• Phrenic arteries

36
Abdominal Aorta Branches

• Celiac trunk
• Superior and inferior mesenteric arteries
• Right and left renal arteries
• Right and left gonadal arteries
• Lumbar arteries
• Right and left common iliac artery
• Femoral artery

37
Abdominal Aorta Branches (contd.)

• Veins
• Found closer to surface than arteries
• Converge with
• Superior vena cava
• Inferior vena cava
• Veins are often named identically to arteries

38
Veins Merging into the Superior Vena Cava

• Radial and ulnar veins form brachial vein
• Empties into axillary vein
• Cephalic vein
• Basilic vein
• Subclavian vein
• Vertebral vein

39
Veins Merging into the Superior Vena Cava
(contd.)

• Internal jugular vein
• Right and left brachiocephalic veins
• Azygos vein

40
Veins Merging into the Inferior Vena Cava

• Anterior and posterior tibial veins
• Peroneal vein
• Popliteal/femoral veins
• External iliac vein
• Great saphenous veins
• Right and left common iliac veins

41
Veins Merging into the Inferior Vena Cava
(contd.)

• Right and left gonadal veins
• Right and left renal veins
• Hepatic portal vein
• Right and left hepatic veins

42
Animation Ventricular Fibrillation

• The following animation illustrates the
  seriousness of an ineffective quivering action of
  the ventricles of the heart, known as ventricular
  fibrillation

Click Here to Play Ventricular Fibrillation
Animation
43
Animation Congestive Heart Failure

• Read about this condition in the Health Alert box
  on Congestive Heart Failure (CHF) in your
  textbook.
• Now watch the congestive heart failure animation.

Click Here to Play Congestive Heart Failure
Animation
44
Summary

• Named the layers of the heart wall
• Named the chambers and valves of the heart
• Described blood flow through the heart
• Described the conduction system of the heart

45
Summary (contd.)

• Discussed the stages of the cardiac cycle
• Compared the anatomy of a vein, artery and
  capillary
• Named the major blood circulatory routes and
  blood vessels