Upload
marianna-riley
View
243
Download
0
Tags:
Embed Size (px)
Citation preview
Copyright 2003 by Mosby, Inc. All rights reserved.
CHAPTER 10
CARDIOVASCULAR SYSTEM
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
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
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
Copyright 2003 by Mosby, Inc. All rights reserved.
Tissues layers of the Heart
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
Copyright 2003 by Mosby, Inc. All rights reserved.
Copyright 2003 by Mosby, Inc. All rights reserved.
Figure 10-4 Blood Vessels
Copyright 2003 by Mosby, Inc. All rights reserved.
The Aorta and major Arteries
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
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
Copyright 2003 by Mosby, Inc. All rights reserved.
Figure 10-2A Structures of the Heart
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
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
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
Copyright 2003 by Mosby, Inc. All rights reserved.
Phases of the Heartbeat
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
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
Copyright 2003 by Mosby, Inc. All rights reserved.
Conduction of Heart
P wave= spread of excitation over atria before contractionQRS wave= spread of excitation over ventricles as contraction occursT wave= electrical recovery and relaxation of ventricles
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
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
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
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
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
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
Copyright 2003 by Mosby, Inc. All rights reserved.
Rheumatic heart
Copyright 2003 by Mosby, Inc. All rights reserved.
Issues and Innovations
• Heart replacement– First artificial heart, Jarvik-7– Heart transplants