1. Copyright 2003 by Mosby, Inc. All rights reserved. CHAPTER 10 CARDIOVASCULAR SYSTEM

2. Copyright 2003 by Mosby, Inc. All rights reserved. Structure and Function Functions of the cardiovascular system –Transports nutrients and oxygen to the body –Transports waste products from the cells to the kidneys for excretion –Distributes hormones and antibodies throughout the body –Helps control body temperature and maintain electrolyte balance

3. Copyright 2003 by Mosby, Inc. All rights reserved. Heart Two-sided, double pump Weighs less than a pound Little bigger than a fist Located between the lungs in the thoracic cavity Positioned partially to the left of the sternum

4. Copyright 2003 by Mosby, Inc. All rights reserved. Tissue Layers of the Heart Endocardium –Smooth layer of cells lining the inside of the heart and forming the valves Myocardium –The thickest layer, consisting of muscle tissue Pericardium –Double membrane that covers the outside of the heart, providing lubrication between the heart and surrounding structures to prevent tissue damage

5. Copyright 2003 by Mosby, Inc. All rights reserved. Tissues layers of the Heart

6. Copyright 2003 by Mosby, Inc. All rights reserved. Blood Vessels Arteries and arterioles –Carry blood away from the heart –The aorta is the largest artery in the body Veins and venuoles –Carry blood back to the heart –The superior and inferior vena cava are the largest veins Capillaries –Microscopic vessels that carry blood between the arterial and venous vessels ; where the gaseous exchanges take place

7. Copyright 2003 by Mosby, Inc. All rights reserved.

8. Figure 10-4 Blood Vessels

9. Copyright 2003 by Mosby, Inc. All rights reserved. The Aorta and major Arteries

10. Copyright 2003 by Mosby, Inc. All rights reserved. Anatomy of the Heart Heart- (cardi/o; coron/o) It is a two-sided double pump; –Rt side of heart send O2 deficient blood to lungs where the blood picks up O2 and releases CO2 –O2 rich blood returns to left side of heart and left side of heart pumps blood to rest of the body Four Chambers: –Two upper chambers called atrium –Two lower chambers called ventricles (ventricul/o) –Septum- divides the right side of the heart from the left side; wall or portion within heart

11. Copyright 2003 by Mosby, Inc. All rights reserved. Heart Valves Four Valves; (valvul/o; vavl/o) –cusps or flaps of valves –Tricuspid- b/w rt atrium and rt ventricle –Pulmonary- b/w rt ventricle and pulmonary artery –Mitral- b/w left atrium and left ventricle –Aortic- prevents return of aortic blood to left ventricle Patent= to open

12. Copyright 2003 by Mosby, Inc. All rights reserved. Figure 10-2A Structures of the Heart

13. Copyright 2003 by Mosby, Inc. All rights reserved. Pulmonary circulation Superior and Inferior Vena Cava Right Atrium Tricuspid Valve Right Ventricle Pulmonary Valve Pulmonary Artery Lungs Pulmonary Vein Left Atrium Mitral Valve Left Ventricle Aortic Valve Aorta (aort/o) To body

14. Copyright 2003 by Mosby, Inc. All rights reserved. Systemic Circulation O2 rich blood leaves heart thru the aorta the largest artery in the body Ascending aorta Descending aorta Arteries Arterioles Tissue Capillaries Venules Veins Superior and Inferior Vena Cava

15. Copyright 2003 by Mosby, Inc. All rights reserved. Physiology of Heart Heartbeat (2 phases) 1. Diastole= relaxation Diastole= short period of rest as the heart fills 2.Systole= contraction phase of heart Systole occurs and blood is pumped away from the heart

16. Copyright 2003 by Mosby, Inc. All rights reserved. Phases of the Heartbeat

17. Copyright 2003 by Mosby, Inc. All rights reserved. Physiology of heart Diastole-Systole Cycle –70-80 times per minute –5 quarts of blood per minute –75 gallons per hour –2000 gallons per day “murmur”= abnormal heart sound

18. Copyright 2003 by Mosby, Inc. All rights reserved. Physiology of the Heart Conduction System –Sinoatrial Node (SA node)= pacemaker of the heart; sensitive tissue in the rt atrium wall that begins the heart beat Posterior of rt atrium Electrical impulse Atria contracts and force blood into the ventricle

19. Copyright 2003 by Mosby, Inc. All rights reserved. Conduction of Heart P wave= spread of excitation over atria before contraction QRS wave= spread of excitation over ventricles as contraction occurs T wave= electrical recovery and relaxation of ventricles

20. Copyright 2003 by Mosby, Inc. All rights reserved. Assessment Techniques Measuring pulse and blood pressure Listening to heart sounds Determining cardiac output Measuring muscle activity with electrocardiography Inserting a cardiac catheter Using echocardiography

21. Copyright 2003 by Mosby, Inc. All rights reserved. Blood Pressure Blood pressure= force that the blood exerts on the arterial walls –Sphygmomanometer- a device to measure blood pressure (sphygm/o=pulse) –First sound= systolic pressure (pressure in the artery when the left ventricle is contracting to force the blood into the aorta); pumping blood to the body –Second sound= diastolic blood pressure (pressure in the artery when the ventricles are relaxing and the heart is filling); when the heart relaxes –Written as a fraction: 120/80= systolic/diastolic

22. Copyright 2003 by Mosby, Inc. All rights reserved. Disorders of the Cardiovascular System (continued) Cardiovascular disease –A general term for the combined effects of arteriosclerosis, atherosclerosis, and related conditions called coronary artery disease Congenital heart disease –A group of disorders that affect about 25,000 newborns each year in the united states –Tetraology of Fallot – 4 separate heart defects Congestive heart failure –The inability of the heart to pump blood adequately to meet the body’s needs

23. Copyright 2003 by Mosby, Inc. All rights reserved. Blood vessel pathology Embolus- floating blood clot or other material in the vessel Atherosclerosis- hardening of the arteries caused by fatty or calcium deposits in the artery walls causing them to thicken - HDL (High-Density Lipoprotein) good - LDL (Low-Density Lipoprotein) bad

24. Copyright 2003 by Mosby, Inc. All rights reserved. Pathological Conditions Ischemia- can lead to a Myocardial Infarction (MI); blood held from an area and can be caused by thrombotic occlusion of a blood vessel Arrhythmia- abnormal heart rhythms Aneurysm- An area of a blood vessel that bulges because of a weakness in the wall Hypertension - High blood pressure Myocardial infarction- Known as a heart attack Phlebitis - An inflammation of a vein, often with formation of a clot

25. Copyright 2003 by Mosby, Inc. All rights reserved. Disorders of the Cardiovascular System (continued) Rheumatic heart disease –A condition in which the heart muscle and valves are damaged by a recurrent bacterial infection that usually begins in the throat Varicose veins –A condition in which veins become enlarged and ineffective

26. Copyright 2003 by Mosby, Inc. All rights reserved. Rheumatic heart

27. Copyright 2003 by Mosby, Inc. All rights reserved. Issues and Innovations Heart replacement – First artificial heart, Jarvik-7 – Heart transplants