1. Essentials of Human Anatomy & Physiology Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slides 11.1 – 11.19 Seventh Edition Elaine N. Marieb Chapter 11 The Cardiovascular System Lecture Slides in PowerPoint by Jerry L. Cook

2. The Cardiovascular System Slide 11.1 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  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  Function: to deliver oxygen and nutrients and to remove carbon dioxide and other waste products

3. The Heart Slide 11.2a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Location:  Mediasternum to the thorax  Pointed apex directed toward left hip  Size: of your fist

4. The Heart Slide 11.2b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 11.1

5. Layers of the Heart: Slide 11.3 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings 1.Pericardium (pericardial sac) – Epicardium a double sac that encloses the heart; outer layer  Visceral pericardium - Next to heart  Parietal pericardium - Outside layer  Serous fluid fills the space between the layers of pericardium

6. The Heart: Heart Wall Slide 11.4 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings 2.Myocardium - middle layer; responsible for heart contraction; mostly cardiac muscle 3.Endocardium – lines the walls of heart chambers; Inner layer (Endothelium)

7. Chambers of the Heart: Slide 11.3 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings 1.Superior chambers – Right and Left Atrium (receiving chambers) 2.Inferior chambers – Right and Left Ventricles (discharging chambers) Interventricular Septum – seperates the R. & L. side of the heart Atroventricular Valves: Tricuspid valve – seperates R. atrium from R. Ventricle Bicuspid (mitral) valve – seperates the L. atrium from L. vetricle

8. The Heart: Valves Slide 11.8  Semilunar valves located between ventricle and artery  Pulmonary semilunar valve – between R. ventricle and pulmonary trunk (lungs)  Aortic semilunar valve – between L. ventricle and aorta (all body tissues)  Valves open as blood is pumped through  Held in place by chordae tendinae (“heart strings”)  Close to prevent backflow

9. External Heart Anatomy Slide 11.5 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 11.2a

10. Internal Heart Anatomy Slide 11.5 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 11.2a

11. Blood Circulation Slide 11.7 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 11.3

12. Circulation of Blood through Heart L. atrium -> bicuspid valve -> L. ventricle -> aortic semilunar valve -> Aorta -> brachiocephalic artery, common carotid artery, subclavin artery, and descending aorta Blood coming from Inferior &Superior Vena Cava R. atrium Tricuspid Valve R. ventricle pulmonary semilunar valve R. & L. pulmonary arteries Lungs R. & L. pulmonary veins Pulmonary trunk

13. The Heart: Associated Great Vessels Slide 11.11 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Aorta  Leaves left ventricle  Pulmonary arteries  Leave right ventricle  Vena cava  Enters right atrium  Pulmonary veins (four)  Enter left atrium

14. Coronary Circulation Slide 11.12 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Blood in the heart chambers does not nourish the myocardium  The heart has its own nourishing circulatory system  Coronary arteries  Cardiac veins  Blood empties into the right atrium via the coronary sinus

15. Operation of Heart Valves Slide 11.10 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 11.4

16. The Heart: Conduction System Slide 11.13a  Intrinsic conduction system (nodal system)  Heart muscle cells contract, without nerve impulses, in a regular, continuous way

17. Components of the Intrinsic System Slide 11.14b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 11.5

18. The Heart: Conduction System  Special tissue sets the pace  Sinoatrial node (SA – node)  Pacemaker – provides stimulus for [ ]  Atrioventricular node (AV – node) – momentarily delays stimulus until atria completely [ ]  Atrioventricular bundle (Bundle of His) – located along interventricular septum  Bundle branches – along interventricular septum  Purkinje fibers – in muscle of ventricular walls; electrical impulse reaches and causes ventricular [ ]  Contraction is initiated by the sinoatrial node  Sequential stimulation occurs at other auto-rhythmic cells

19. Electrocardiogram = EKG or ECG Instrument that records the electrical current that flows along the intrinsic system during a cardiac cycle. Electrocardiograph- graphical representation of the electrical changes (depolarization /repolarization) occurring during a cardiac cycle Three deflection waves produced from an EKG:

20. Electrocardiogram = EKG or ECG P-wave – depolarization of atria QRS-wave – depolarization of ventricles; masks repolarization of atria T-wave – repolarization of ventricles PR-segment – no current flow; AV-nodal delay; complete depolarization of atria ST-Segment- no current flow; complete depolarization of ventricles

21. The Heart: Cardiac Cycle Cardiac cycle – refers to the events of one complete heart beat, during which both atria and ventricles contract and relax Slide 11.16 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Atria contract simultaneously as well as the ventricles  Atria relax, then ventricles contract  Systole = contraction  Diastole = relaxation

22. The Heart: Cardiac Cycle Slide 11.17 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Cardiac cycle – events of one complete heart beat Avg. heart beats 75 beats/min. Length of 1 cardiac cycle = 0.8 sec Events of cardiac cycle:  Mid-to-late diastole – blood flows into ventricles  Ventricular systole – blood pressure builds before ventricle contracts, pushing out blood  Early diastole – atria finish re-filling, ventricular pressure is low

23. Filling of Heart Chambers – the Cardiac Cycle Slide 11.15 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 11.6

24. Heart Sounds: Described as two syllables “lub” and “dup” First hear sound “lub” associated w/ closing of the AV valves; longer and louder Second heart sound “dup” associated w/ closing of semilunar valves at the end of systole; shorter and sharp

25. Blood Pressure: Described as two syllables “lub” and “dup” First hear sound “lub” asssociated w/ closing of the AV valves; longer and louder Second heart sound “dup” associated w/ closing of semilunar valves at the end of systole; shorter and sharp

26. Blood Pressure: BP = systolic pressure / diastolic pressure mmHg Systolic pressure – pressure exerted on the arteries at the peak of ventricular ejection Diastolic pressure – reflects the pressure during ventricular relaxation Avg. BP reading: 120/80 mmHg ConditionsSystolic pressureDiastolic pressure Normal Pressure< 139<89 Borderline140-15990-94 Hypertension>160>95 Hypotension<99<60

27. Pulse: Alternating surges of pressure due to expansion and recoiling of an artery that occurs with each contraction and relaxation of the ventricles Superficial Pulse points: Popliteal artery Common carotid artery Radial artery Temporal artery Femoral artery Facial artery Brachial artery Posterior tibial artery Dorsalis pedis artery

28. The Heart: Cardiac Output Slide 11.18 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Cardiac output (CO)  Amount of blood pumped by each side of the heart in one minute; product of :  CO = (heart rate [HR]) x (stroke volume [SV])  Stroke volume  Volume of blood pumped by each ventricle in one contraction  (Increases as the force of ventricular contraction increases  If normal resting heart rate is 75beats/min and stroke volume is 70 ml/beat, then CO = 7250 ml/min. Since normal adult blood volume is about 5000mL, the entire blood supply passes through the body once each minute.)

29. Cardiac Output Regulation Slide 11.19 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 11.7

30. Electrocardiogram = EKG Produces 3 deflection waves: P-wave QRS-wave T-wave

31. The end