1. PowerPoint ® Lecture Slide Presentation by Patty Bostwick-Taylor, Florence-Darlington Technical College Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings PART A 11 The Cardiovascular System

2. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Cardiovascular System  A closed system of the heart and blood vessels  The heart pumps blood  Blood vessels allow blood to circulate to all parts of the body  The function of the cardiovascular system is to deliver oxygen and nutrients and to remove carbon dioxide and other waste products

3. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart  Location  Thorax between the lungs in the inferior mediastinum  Orientation  Pointed apex directed toward left hip  Base points toward right shoulder  About the size of your fist  Weighs less than a pound

4. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart Figure 11.1a–b

5. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart Figure 11.1c

6. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart Figure 11.2a

7. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart: Coverings  Pericardium—a double-walled sac  Fibrous pericardium is loose and superficial  Serous membrane is deep to the fibrous pericardium and composed of two layers  Visceral pericardium  Next to heart; also known as the epicardium  Parietal pericardium  Outside layer that lines the inner surface of the fibrous pericardium  Serous fluid fills the space between the layers of pericardium

8. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart: Heart Wall Figure 11.2b

9. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart: Heart Wall  Three layers  Epicardium  Outside layer  This layer is the visceral pericardium  Connective tissue layer  Myocardium  Middle layer  Mostly cardiac muscle  Endocardium  Inner layer  Endothelium

10. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart: Heart Wall Figure 11.2b

11. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart: Heart Wall Figure 11.2c

12. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart: Chambers  Right and left side act as separate pumps  Four chambers  Atria  Receiving chambers  Right atrium  Left atrium  Ventricles (thick-walled)  Discharging chambers (pumps of the heart)  Right ventricle  Left ventricle Use pages 365 to find answers.

13. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart: Chambers Figure 11.2c

14. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Differences in Right and Left Ventricles Figure 11.4

15. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart: Septa  Interventricular septum  Separates the two ventricles  Interatrial septum  Separates the two atria

16. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart: Chambers Figure 11.2c

17. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart: Valves  Allow blood to flow in only one direction to prevent backflow  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 Use pg 366 to help answer notes

18. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart: Valves Figure 11.2c

19. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart: Valves  AV valves  Anchored in place by chordae tendineae (“heart strings”)  Open during heart relaxation and closed during ventricular contraction  Semilunar valves  Closed during heart relaxation but open during ventricular contraction  Notice these valves operate opposite of one another to force a one-way path of blood through the heart

20. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Figure 11.5a, step 1 Blood returning to the atria, puts pressure against AV valves; the AV valves are forced open Ventricles Operation of the AV valves AV valves open (a)

21. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Figure 11.5a, step 2 Blood returning to the atria, puts pressure against AV valves; the AV valves are forced open As the ventricles fill, AV valve flaps hang limply into ventricles Ventricles Operation of the AV valves AV valves open (a)

22. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Figure 11.5a, step 3 Blood returning to the atria, puts pressure against AV valves; the AV valves are forced open As the ventricles fill, AV valve flaps hang limply into ventricles Atria contract, forcing additional blood into ventricles Ventricles Operation of the AV valves AV valves open (a)

23. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Figure 11.5a, step 4 Ventricles contract, forcing blood against AV valve flaps (a)

24. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Figure 11.5a, step 5 Ventricles contract, forcing blood against AV valve flaps AV valves close AV valves closed (a)

25. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Figure 11.5a, step 6 Ventricles contract, forcing blood against AV valve flaps AV valves close Chordae tendineae tighten, preventing valve flaps from everting into atria AV valves closed (a)

26. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Figure 11.5b, step 1 As ventricles contract and intraventricular pressure rises, blood is pushed up against semilunar valves, forcing them open Aorta Pulmonary trunk Semilunar valve open Operation of the semilunar valves (b)

27. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Figure 11.5b, step 2 As ventricles contract and intraventricular pressure rises, blood is pushed up against semilunar valves, forcing them open Aorta Pulmonary trunk Semilunar valve open Semilunar valve closed As ventricles relax, and intraventricular pressure falls, blood flows back from arteries, filling the leaflets of semilunar valves and forcing them to close Operation of the semilunar valves (b)

28. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Systemic and Pulmonary Circulations  Systemic circulation  Oxygen-rich blood drains from the lungs & flows to the left side of the heart through the body tissues  Delivers oxygen rich blood & nutrients & removes wastes  Now goes back to the right side of the heart  Pulmonary circulation  Oxygen-poor blood flows from the right side of the heart to the lungs  Picks up more oxygen and unloads carbon dioxide  Now goes back to the left side of the heart

29. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Systemic and Pulmonary Circulations Figure 11.3 Systemic circulation Oxygen-rich blood drains from the lungs & flows to the left side of the heart through the body tissues and back to the right side of the heart Pulmonary circulation Oxygen-poor blood flows from the right side of the heart to the lungs and back to the left side of the heart

30. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart: Associated Great Vessels  Arteries  Aorta  Leaves left ventricle  Pulmonary arteries  Leave right ventricle

31. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart: Associated Great Vessels  Veins  Superior and inferior venae cavae  Enter right atrium  Pulmonary veins (four)  Enter left atrium

32. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart: Associated Great Vessels Figure 11.2c

33. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Blood Flow Through the Heart 1.Blood that is low in oxygen and high in CO 2 enters right atrium through the superior and inferior venae cavae 2.From (contraction) right atrium, through the tricuspid valve, blood travels to the right ventricle 3.From (contraction) the right ventricle, blood leaves the heart as it passes through the pulmonary semilunar valve into the pulmonary trunk 4.Pulmonary trunk splits into right and left pulmonary arteries that carry blood to the lungs

34. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Blood Flow Through the Heart 5. Oxygen is picked up and carbon dioxide is dropped off by blood in the lungs 6. Oxygen-rich blood returns to the heart through the four pulmonary veins 7. Blood enters the left atrium and travels through the bicuspid (mitral) valve into the left ventricle 8. From the left ventricle, (wall contracts) blood leaves the heart via the aortic semilunar valve and aorta 9. Oxygenated blood flows to all body tissues

35. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Systemic and Pulmonary Circulations Figure 11.3

36. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Coronary Circulation  Blood in the heart chambers does not nourish the myocardium  The heart has its own nourishing circulatory system consisting of  Coronary arteries—branch from the aorta to supply the heart muscle with oxygenated blood  Cardiac veins—drain the myocardium of blood  Coronary sinus—a large vein on the posterior of the heart, receives blood from cardiac veins  Blood empties into the right atrium via the coronary sinus

37. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Physiology of the Heart: Conduction System  Intrinsic conduction system (nodal system)  Sets the heart’s basic rhythm  This system is composed of special tissue that is a cross between nervous & muscle tissue.  Heart muscle cells contract, without nerve impulses, in a regular, continuous way  One direction  atria to ventricles  Forces a contraction rate of apprx. 75 bpm

38. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart: Conduction System  Special tissue sets the pace  Sinoatrial node = SA node (“pacemaker”), is in the right atrium  Atrioventricular node = AV node, is at the junction of the atria and ventricles  Atrioventricular bundle = AV bundle (bundle of His), is in the interventricular septum  Bundle branches are in the interventricular septum  Purkinje fibers spread within the ventricle wall muscles

39. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Coronary Circulation  Angina pectoris- crushing chest pain caused by oxygen deprivation of the myocardium  this pain is a warning sign  If angina is prolonged the oxygen-deprived heart cells may die, forming an infarct.  Myocardial infarction-a “heart attack” or “coronary”-- caused by oxygen-deprivation of the myocardium.

40. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Heart Contractions Figure 11.6

41. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Heart Contractions  Contraction is initiated by the sinoatrial node (SA node)  Sequential stimulation occurs at other autorhythmic cells  Force cardiac muscle depolarization in one direction—from atria to ventricles

42. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Heart Contractions  Once SA node starts the heartbeat  Impulse spreads to the AV node  Then the atria contract  At the AV node, the impulse passes through the AV bundle, bundle branches, and Purkinje fibers  Blood is ejected from the ventricles to the aorta and pulmonary trunk as the ventricles contract

43. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Heart Contractions Figure 11.6

44. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Heart Contractions  Ischemia- lack of adequate blood supply to the heart muscle may lead to fribillation  Fibrillation-rapid uncoordinated shuddering of heart muscle  It is the major cause of death from heart attacks in adults  Tachycardia—rapid heart rate over 100 beats per minute  Bradycardia—slow heart rate less than 60 beats per minute

45. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart: Cardiac Cycle  Atria contract simultaneously  Atria relax, then ventricles contract  Systole = contraction  Diastole = relaxation

46. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Filling Heart Chambers: Cardiac Cycle Figure 11.7 Atrial contraction Mid-to-late diastole (ventricular filling) Ventricular systole (atria in diastole) Early diastole Isovolumetric contraction phase Ventricular ejection phase Isovolumetric relaxation Ventricular filling Left atrium Right atrium Left ventricle Right ventricle

47. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Filling Heart Chambers: Cardiac Cycle Figure 11.7, step 1a Mid-to-late diastole (ventricular filling) Ventricular filling Left atrium Right atrium Left ventricle Right ventricle

48. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Filling Heart Chambers: Cardiac Cycle Figure 11.7, step 1b Atrial contraction Mid-to-late diastole (ventricular filling) Ventricular filling Left atrium Right atrium Left ventricle Right ventricle

49. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Filling Heart Chambers: Cardiac Cycle Figure 11.7, step 2a Atrial contraction Mid-to-late diastole (ventricular filling) Ventricular systole (atria in diastole) Isovolumetric contraction phase Ventricular filling Left atrium Right atrium Left ventricle Right ventricle

50. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Filling Heart Chambers: Cardiac Cycle Figure 11.7, step 2b Atrial contraction Mid-to-late diastole (ventricular filling) Ventricular systole (atria in diastole) Isovolumetric contraction phase Ventricular ejection phase Ventricular filling Left atrium Right atrium Left ventricle Right ventricle

51. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Filling Heart Chambers: Cardiac Cycle Figure 11.7, step 3 Atrial contraction Mid-to-late diastole (ventricular filling) Ventricular systole (atria in diastole) Early diastole Isovolumetric contraction phase Ventricular ejection phase Isovolumetric relaxation Ventricular filling Left atrium Right atrium Left ventricle Right ventricle

52. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart: Cardiac Cycle  Cardiac cycle—events of one complete heart beat  Mid-to-late diastole—blood flows from atria into ventricles  Ventricular systole—blood pressure builds before ventricle contracts, pushing out blood  Early diastole—atria finish refilling, ventricular pressure is low

53. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart: Cardiac Output  Cardiac output (CO)  Amount of blood pumped by each side (ventricle) of the heart in one minute  Stroke volume (SV)  Volume of blood pumped by each ventricle in one contraction (each heartbeat)  Usually remains relatively constant  About 70 mL of blood is pumped out of the left ventricle with each heartbeat  Heart rate (HR)  Typically 75 beats per minute

54. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings The Heart: Regulation of Heart Rate  Increased heart rate  Sympathetic nervous system  Crisis  Low blood pressure  Hormones  Epinephrine  Thyroxine  Exercise  Decreased blood volume  Decreased heart rate  Parasympathetic nervous system  High blood pressure or blood volume  Decreased venous return

55. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Major Arteries of the Body  Aorta  Largest artery in the body  Leaves from the left ventricle of the heart  Regions  Ascending aorta—leaves the left ventricle  Aortic arch—arches to the left  Thoracic aorta—travels downward through the thorax  Abdominal aorta—passes through the diaphragm into the abdominopelvic cavity  Arterial branches of the ascending aorta  Right and left coronary arteries serve the heart

56. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Major Arteries of Systemic Circulation  Arterial branches of the aortia arch (BCS)  Brachiocephalic trunk splits into the  Right common carotid artery  Right subclavian artery  Left common carotid artery splits into the  Left internal and external carotid arteries  Left subclavian artery branches into the  Vertebral artery  In the axilla, the subclavian artery becomes the axillary artery  brachial artery  radial and ulnar arteries

57. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Major Arteries of Systemic Circulation Arteries you must know: External carotid Brachiocephalic trunk Common carotid Subclavian Coronary Thoracic Brachial Abdominal Common iliac Femoral Renal Anterior tibial

58. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Major Veins of Systemic Circulation  Superior and inferior vena cava enter the right atrium of the heart  Superior vena cava drains the head and arms  Inferior vena cava drains the lower body

59. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Major Veins of Systemic Circulation  Veins draining into the superior vena cava  Radial and ulnar veins  brachial vein  axillary vein  These veins drain the arms  Cephalic vein drains the lateral aspect of the arm and empties into the axillary vein  Basilic vein drains the medial aspect of the arm and empties into the brachial vein  Basilic and cephalic veins are jointed at the median cubital vein (elbow area)

60. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Major Veins of the Systemic Circulation  Veins draining into the superior vena cava  Subclavian vein receives  Venous blood from the arm via the axillary vein  Venous blood from skin and muscles via external jugular vein  Vertebral vein drains the posterior part of the head  Internal jugular vein drains the dural sinuses of the brain

61. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Major Veins of Systemic Circulation Veins you must know: External jugular Superior vena cava Great cardiac basilic Subclavian R&L brachiocephalic Brachial Radial External iliac Femoral Great saphenous

62. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Blood Pressure  Measurements by health professionals are made on the pressure in large arteries  Systolic—pressure at the peak of ventricular contraction  Diastolic—pressure when ventricles relax  Write systolic pressure first and diastolic last (120/80 mm Hg)  Pressure in blood vessels decreases as distance from the heart increases

63. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Comparison of Blood Pressures in Different Vessels

64. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Variations in Blood Pressure  Normal human range is variable  Normal  140–110 mm Hg systolic  80–75 mm Hg diastolic  Hypotension  Low systolic (below 110 mm Hg)  Often associated with illness  Hypertension  High systolic (above 140 mm Hg)  High diastolic (above 90 mm Hg)  Can be dangerous if it is chronic

65. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Measuring Arteriole BP