1. The heart & blood

2. Cardiovascular System
Blood
Heart
Blood vessels
Arteries - bring blood away from heart
Veins – bring blood to heart
Capillaries – smallest vessels where oxygen/nutrient exchange occurs

3. Heart Wall
Located in the mediastinum within the thoracic cavity (pericardial cavity)
Protected by serous membrane called pericardium
Epicardium – forms outermost layer of cardiac wall
Myocardium – composed of cardiocytes
Endocardium – thin layer that covers chambers of heart

5. External Anatomy of the Heart
Four chambers  2 ventricles , 2 atria
Atria: “receiving” chambers and return blood from veins
Ventricles: “pumping” chambers and distribute blood to lungs and tissues
Pulmonary circuits  directs deoxygenated blood to lungs
Systemic circuit  takes oxygenated blood to the body

6. Brachiocephalic
Carotid
Subclavian
Vena Cava
Aorta
Pulmonary Arteries
Pulmonary Trunk
Pulmonary Veins
Left Atrium
Semilunar Valves & Aortic Valve
Right Atrium
Bicuspid/Mitral Valve
Tricuspid/AV Valve
Left Ventricle
Right Ventricle

7. Coronary Circulation The heart can NEVER completely rest
It needs to nourish itself
Systemic circulation  coronary circulation: supplies myocardium with oxygen for muscle contraction

8. Left Coronary Artery
Right Coronary Artery
Circumflex Artery
Marginal Artery
Anterior IV Branch
Posterior IV Branch

9. Coronary Circulation cont’d
The arteries are circulating oxygenated blood
Cardiac veins collect the deoxygenated blood from myocardium
Veins merge at the coronary sinus
Empties deoxygenated blood into the right atrium

10. How can the heart contract?
Cardiac muscle tissue is “autorhythmic”
Does NOT need stimulation from nerves
Brain only dictates how fast the heart contracts
Pacemaker  Sinoatrial node (SA node)
Sets the pace by sending an electrical impulse to other nodal cells
SA Node
AV Node

12. Composition and Function
Regulates pH and electrolyte levels
Supplies cells with nutrients and oxygen
Manufacture substances needed for defense against bacteria
Ability to change from liquid to gel in clot formation for injury repair
Classified into:
Formed elements
Plasma

14. Formed Elements
Red blood cells (erythrocytes)  oxygen transport via hemoglobin
White blood cells (leukocytes)  phagocytes, scavenger cells that destroy foreign substances
Eosinophils
Basophils – release histamine
Platelets  injury mediators / blood clotting
Normal bleeding time 0-7 min

16. Hematocrit Equivalent to the RBC concentration in the blood
Used to determine possible anemia
Can you still be anemic with a normal RBC concentration?
Yes

17. Hemoglobin RBC protein responsible for oxygen transport
Measuring the hemoglobin can give you information on oxygen carrying capacity of the blood

18. Cholesterol is carried in the blood
Atherosclerosis: disease in which blood vessels become increasingly occluded or blocked by plaques
High cholesterol levels can lead to atherosclerosis
Normal value: is mg per 100 ml of blood
Good vs Bad Cholesterol
HDL vs LDL

19. How does high cholesterol affect the heart?

20. Blood Pressure
Pressure of the circulating blood against your vessel walls
Systolic – when heart contracts and pushes through arteries
Diastolic – measures pressure when ventricles are filling up / in between beats
Normal is about 120/80
Hypertension  silent killer

21. Blood Typing – ABO & RH Blood type is genetically inherited
Based on the type of antigen marker molecules on surface of blood cells
Rh surface antigen (D antigen)  some people have it, some do not

23. RhoGAM

24. Due next week
Chapter 29 & 30