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Chapter 11
Cardiovascular System
Cardiovascular System
• Blood Vessels- (angi/o); (vas/o; vascul/o)
– 1. Arteries (arter/o; arteri/o)
• The large vessels that lead away from the heart
• Walls of are made of connective tissues, muscle
tissue, elastic fibers, and epithelial cells
• Elastic walls allow for expansion as heartbeat forces
blood into the system
• Small branches of arteries are called arterioles.
Arterioles are thinner and carry blood to the tiniest
of blood vessels, the capillaries
Blood Vessels
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Aneurysm- a local widening of an artery
Hypertension- high blood pressure
Peripheral vascular disease- claudication
Raynaud phenomenon
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
Atherosclerosis.
Fig. 11-11.
(Modified from Kumar V, Cotran R, Robbins SL: Basic Pathology, 6th ed.
Philadelphia, WB Saunders, 1997, page 319.)
Copyright © 2001 by W. B. Saunders Company. All rights reserved.
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Capillaries
• Walls are only one endothelial cell thick
• Carry nutrient-rich, oxygenated blood from
the arteries and arterioles to the body cells
• Waste products (CO2 and H2O) pass out of
the cell and into the thin-wall capillaries
• Waste-filled blood then flows back to the
heart in venules, which branch to form
veins
Veins (phleb/o; ven/o)
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Thinner walled than arteries
Conduct blood toward the heart from the tissues
Lower pressure than arteries
Veins have valves to prevent backflow of blood and
keep the blood moving in one direction
• Muscular action helps movement of blood
• Varicose Veins
Phlebitis- inflammation of a vein
Phlebotomy- incision of a vein
Blood vessels.
Fig. 11-1.
(Some parts modified from Damjanov I: Pathology for the Health-Related Professions.
Philadelphia, WB Saunders, 1996, page 155.)
Copyright © 2001 by W. B. Saunders Company. All rights reserved.
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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
• Size of your fist
• Lies in the thoracic cavity
• Four Chambers:
– Two upper chambers called atrium
– Two lower chambers called ventricles (ventricul/o)
Anatomy of the heart
• 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
Anatomy of the heart
• Septum- divides the right side of the heart from the
left side; wall or portion within heart
• Three layers of the heart:
– Endocardium- smooth cells that line the inside of the
heart and valves
– Myocardium- the thickest layer, consists of muscle
tissue; this layer pumps blood throughout the body
– Pericardium (pericardi/o)- double membrane that
covers the outside of the heart. Prevents damage from
ribs and surrounding structures (“pads the heart”)
*Cardiomyopathy- disease of heart muscle
The walls of the heart and
pericardium.
Fig. 11-5.
Copyright © 2001 by W. B. Saunders Company. All rights reserved.
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Fig. 11-4.
(Modified from Damjanov I: Pathology for the Health-Related Professions.
Philadelphia, WB Saunders, 1996, page 154.)
Copyright © 2001 by W. B. Saunders Company. All rights reserved.
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Pulmonary Circulation
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Superior and Inferior Vena Cava
Right Atrium
Tricuspid Valve
Right Ventricle
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Pulmonary Valve
Pulmonary Artery
Lungs
Pulmonary Vein
Left Atrium
Mitral Valve
Left Ventricle
Aortic Valve
Aorta (aort/o)
To body
The aorta and arteries.
Fig. 11-3.
Copyright © 2001 by W. B. Saunders Company. All rights reserved.
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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
Physiology of the Heart
•
Heartbeat (2 phases)
1. Diastole= relaxation
– Blood comes from the vena cava and
pulmonary veins
– Tricuspid and mitral valves open
– Pulmonary and aortic valves closed
2. Systole= contraction phase of heart
- Ventricles contract to pump blood via
pulmonary artery and aorta
- Tricuspid and mitral valve are closed
Phases of the heartbeat.
Fig. 11-7.
Copyright © 2001 by W. B. Saunders Company. All rights reserved.
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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
Heart Sounds
“lub” sound= closure of tricuspid valve and mitral valves
at the beginning of systole and is first heart sound
“dub” sound= closure of aortic and pulmonary valves at
end of systole and is second heart sound
“murmur”= abnormal heart sound
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
Physiology of 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
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
– Heart block (AV block); failure of proper conduction of
impulses thru AV node to AV Bundle of HIS;
pacemakers can help
– Flutter- rapid but regular contraction of atria or
ventricles
– Fibrillation- rapid, random, ineffectual contraction of
the heart
– Palpitations- uncomfortable sensations in the chest
Pathological Conditions
• Endocarditis- inflammation of inner lining
of heart due to bacteria
• Congestive Heart Failure- heart is unable to
pump required amount of blood
• Coronary Artery Disease- (CAD); blockage of
arteries surrounding the heart and leads to
ischemia
– MI= Myocardial Infarction (Heart Attack)
– Angina pectoris= chest pain; nitroglycerin can
help: vasodilator (relaxes vessels)
Pathological Conditions
• Hypertensive heart disease- high blood
pressure
• Mitral Valve Prolapse (MVP)- improper
closure of the mitral valve
• Murmur- extra heart sound between beats
• Pericarditis- inflammation of membrane
surrounding heart
• Rheumatic heart disease- heart disease
caused by strep infection
• Cyanosis- bluish coloration of skin
Laboratory Procedures
• Ultrasound– Doppler ultrasound: sound waves on a blood vessel
– Echocardiography (ECHO)- pulses of high-frequency
sound waves and shows valves, chambers, and surfaces
of the heart
• X-Ray
– Angiography- dye injected into blood steam and x-ray
taken of heart and vessels
– Digital subtraction angiography (DSA)x-ray done then dye injected and x-ray taken; a
comparison is then done
Echocardiography
Echocardiogram
Procedures
• Cardiac Cath- incision in the groin and a catheter is
threaded into the circulatory system to the heart
• Cardioversion (defibrillation)- discharge of electricity
applied across the chest to stop arrhythmia
• Coronary Bypass surgery- (CABG) vessel grafts are
anastomosed to detour around blockages
• Electrocardiography (EKG,ECG)- recording of the
electricity of the heart
– Normal sinus rhythm= normal heart beat
Coronary artery bypass graft
(CABG) surgery.
Fig. 11-23.
Copyright © 2001 by W. B. Saunders Company. All rights reserved.
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Placement of an intracoronary
artery stent.
Fig. 11-25ABC.
Copyright © 2001 by W. B. Saunders Company. All rights reserved.
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