Afterloadload against which an activated muscle must try to shorten; greater afterloads result in lower velocities.
Arteriovenous anastomosiscommunication between an artery and a vein, either as a congenital anomaly (capillaries), or as a surgically produced link between vessels.
Automaticityrefers to the heart’s ability to generate its own intrinsic electrical rhythm.
Barorecptorspressure-sensitive nerve endings in the walls of the atria of the heart, the vena cava, the aortic arch, and the carotid sinus.
Cardiac Outputvolume of blood pumped per minute by the heart.
Cardiac Tamponadecompression of the heart caused by the collection of blood, fluid, or gas under pressure in the pericardium.
Chemoreceptorssensory nerve cells activated by changes in the chemical environment surrounding it; the chemoreceptors in the carotid artery are sensitive to PCO2 in the blood, signaling the respiratory center in the brain to increase or decrease ventilation.
Congestive heart failurean abnormal condition that reflects impaired cardiac output, caused by MI, ischemic heart disease, or cardiomyopathy.
Contractilityproperty of muscle tissue to shorten in response to a stimulus, usually electrical.
end-diastolic volume (EDV)volume of blood remaining in the ventricles just prior to contraction.
end-systolic volume (ESV)volume of blood in the ventricles at the end of contraction (systole)
Frank-Starling LawThe more a muscle fiber is stretched, the greater is the tension the muscle fiber generates when contracted.
negative feedback loopwhen the output of a system acts to oppose changes to the input of the system, with the result that the changes are attenuated and output is balanced.
negative inotropismDECREASE in contractility of the heart
pericardiumfibrous, serous sac that surrounds the heart and roots of the great vessels.
positive inotropismINCREASE in the contractility of the muscle tissue.
Preloadpressure stretching the ventricular walls at the onset of ventricular contraction.
Regurgitationbackward flow of the blood through an incompetent valve of the heart.
Stenosisnarrowing of a valve or vessel
Stroke Volume (SV)volume of blood ejected by the left ventricle during each contraction.
vasoconstrictionnarrowing of the blood vessels.
vasodilationwidening or distension of blood vessels, particularly arterioles, usually caused by nerve impulses or certain drugs that relax smooth muscle in the walls of the blood vessels.
1.2 major subdivisions of the vascular systemsystemic vasculature and pulmonary vasculature
2.3 major components of the systemic vasculaturearterial system, capillary system, and venous system.
3.4 mechanisms to aid venous return to the heart1. sympathetic venous tone 2. skeletal muscle pumping 3. cardiac suction 4. thoracic pressure differences caused by respiratory efforts
4.Afterloadforce against which the heart must pump
5.Although the heart is a single organ it functions as…2 separate pumps
6.anatomic shuntwhenever venous blood mixes with arterial blood the overall o2 count decreases.
7.Arterial systemconsists of large, highly elastic, low-resistance arteries and small muscular arterioles of varying resistance
8.arteriovenous anastomosisa direct communication between vessels
9.The atrioventricular valves close duringsystole (contraction of the ventricles), preventing backflow of blood into the atria. Closure of these valves provides a critical period of isovolemic contraction, during which chamber pressures quickly increase just before ejection of the blood.
10.baroreceptorsrespond to pressure changes
11.capillary systemmicrocirculation maintains a constant exchange of nutrients and waste products for the cells and tissues of the body
12.chemoreceptorsrespond to changes in blood chemistry
13.CHFcongestive heart failure
14.Common valve problems are…regurgitation and stenosis
15.Conductivitythe ability of myocardial tissue to spread, or radiate electrical impulses
16.Contractilityin response to an electrical impulse is the primary function of the myocardium
17.coronary sinuspasses left to right across the posterior surface of the heart. the coronary sinus empties into the right atrium between the opening of the inferior vena cava and the tricuspid valve
18.dicrotic notchcaused by elastic recoil of the arteries
19.During cardiac contractions blood is…ejected out of the heart and to the lungs through right valves and to the body through the left valves
20.ESVend systolic volume…
21.Excitabilitythe ability of cells to respond to electrical, chemical, or mechanical stimulation
22.Externally, surface grooves calledsulci mark the boundaries of the heart chambers.
23.factors of afterloadtension in the ventricular wall and peripheral resistance
24.Frank- Starling Lawthe more cardiac fiber is stretched, the greater the tension it generates when contracted
25.The free ends of the atrioventricular valves are anchored to papillary muscles of the endocardium bychordae tendineae cordis
26.A healthy heart muscle requires how much blood supply?1/20 to function properly
27.The heart ishollow, four-chambered muscular organ approximately the size of a fist. It is positioned obliquely in the middle compartment of the mediastinum of the chest, just behind the sternum (Figure 9-1). Approximately two-thirds of the heart lies to the left of the midline of the sternum between the points of attachment of the second through the sixth ribs. The apex of the heart is formed by the tip of the left ventricle and lies just above the diaphragm at the level of the fifth intercostal space to the left. The base of the heart is formed by the atria and projects to the patient’s right lying just below the second rib. It is level with the second rib below the sternum. Posteriorly, the heart rests on the bodies of the fifth to the eighth thoracic vertebrae. Because of its position between the sternum and the spine, rhythmic compression of the heart can maintain blood flow during cardiopulmonary resuscitation.
28.The heart is enclosed in a double-walled sac called the pericardium. The outer fibrous layer consists of tough connective tissue. The inner serous layer is thinner and more delicate. The structure of the pericardium can be summarized as follows:1 Fibrous pericardium: Tough, loose-fitting, and inelastic sac surrounding the heart

2 Serous pericardium: Consisting of two layers:

a Parietal layer: Inner lining of the fibrous pericardium

b Visceral layer or epicardium: Covering the outer surface of the heart and great vessels

29.the heart’s circulatory systemcoronary circulation, provides an extensive network of branches to all myocardial tissue
30.The heart wall consists of three layers:(1) outer epicardium, (2) middle myocardium, and (3) inner endocardium
31.HRHeart Rate
32.Inercalated discscardiac fibers that are separated by irregular transverse thickenings of the sarcolemma. They provide structural support and aid electrical conduction between fibers
33.Inherent rhythmicityaka automaticity is the unique ability of the cardiac muscle to initiate a spontaneous impulse
34.Left ventricular aids….Right ventricular contraction
35.MAPMean arterial pressure= cardiac output x Vascular resistance
36.metabolic controlinvolves the relationship between vascular smooth muscle tone and the level of local cellular metabolites
37.Myocardial tissue possesses 4 key properties1. excitability 2. inherent rhythmicity 3. conductivity 4. contractility
38.myogenic controlinvolves relationship between vascular smooth muscle tone and perfusion pressure, ensures relatively constant flows to the capillary beds despite changes in perfusion pressures
39.negative feedback loopstimulation of a receptor causes an opposite response by effector
40.the performance of the heart as a pump depends on…the ability to initiate and conduct electrical impulses, 2. to contract synchronously the heart;s muscle fibers quickly and efficiently.
41.Positive intropisma higher SV for a given preload indicates a state of increased contractility
42.precapillare sphincterscapillaries smooth muscle rings at their proximal ends
43.pulmonary vasculaturebegins with the pulmonary trunk out of the right ventricle and ends in the left atrium
44.PVRMean pulmonary artery pressure- left atrial pressure/ cardiac output… PULMONARY VASCULAR RESISTANCE
45.regurgitationthe backflow of blood through an incompetent or a damaged valve
46.sarcolemmaindividual fibers that are enclosed in a membrane surrounded by a rich capillary network
47.stenosisa pathologic narrowing or constriction of a valve outlet, which causes increased pressure in the proximal chamber and vessels
48.Summary ChecklistThe cardiovascular system consists of the heart and a complex vascular network that work together to maintain homeostasis by continually distributing and regulating blood flow throughout the body.

• Specialized mechanical and electrical properties of cardiac tissue, combined with internal and external control mechanisms, provide the basis for coordinated cardiac function.

• The vascular system is regulated by local and central control mechanisms.

• Cardiac output is primarily determined by four factors: preload, afterload, contractility, and HR.

• Increased HR decreases cardiac output by decreasing filling times (decreasing EDV) and decreasing contraction times—hence increasing ESV.

• The vascular network assumes an active role in the control and distribution of blood flow.

• The heart and the vascular systems work together in a coordinated fashion to ensure that all body tissues receive sufficient blood to meet their metabolic needs.

• In a healthy subject, blood pressure is regulated by changing the volume of circulating blood, changing the capacity of the vascular system, or changing both.

• Under conditions of increased demand, special compensatory mechanisms are called on to maintain stable blood flow.

• Failure of cardiovascular control mechanisms often requires the intervention of RTs to help restore and maintain normal function.

49.Support for the four interior chambers and valves of the heart is provided by four atrioventricular rings, which form a fibrous “skeleton.”Each ring is composed of dense connective tissue termed anulus fibrosis cordis. This connective tissue, besides providing an anchoring structure for the heart valves, electrically isolates the atria from the ventricle. No impulses can be transmitted through the heart tissue from the atria to the ventricles.
50.SVSTROKE VOLUME… Cardiac output = sv x hr
51.SVR calculationmean aortic pressure- right atrial pressure/ cardiac output….SYSTEMIC VASCULAR RESISTANCE.
52.systemic vasculaturebegins with the aorta on the left ventricle and ends in the right atrium
53.thesbesian veinsempty directly into all the heart chambers, any blood coming through these veins that enter the left atrium or ventricle mixes with arterial blood coming from the lungs.
54.A thin layer of fluid called the pericardial fluid separatesthe two layers of the serous pericardium. This layer of fluid helps minimize friction as the heart contracts and expands within the pericardium. Inflammation of the pericardium results in a clinical condition called pericarditis. An abnormal amount of fluid can accumulate between the layers resulting in a pericardial effusion. A large pericardial effusion may affect the pumping function of the heart resulting in a cardiac tamponade. A cardiac tamponade compresses the heart muscle leading to a serious decrease in blood flow to the body, which ultimately may lead to shock and death.
55.The two atrial chambers are thin-walled “cups” of myocardial tissueseparated by an interatrial septum. On the right side of the interatrial septum is an oval depression called the fossa ovalis cordis, which is the remnant of the fetal foramen ovale, the shunt that allowed blood to enter the left atrium from the right atrium before birth. In addition, each atrium has an appendage, or auricle, the function of which is unknown. In the presence of cardiac dysrhythmias, blood flow can become stagnant on these appendages leading to the formation of thrombi.
56.The two lower heart chambers, or ventricles, make up the bulk of the heart’s muscle mass and do most of the pumping that circulates the bloodThe mass of the left ventricle is normally about two-thirds larger than the mass of the right ventricle and has a spherical appearance when viewed in anteroposterior cross section. The right ventricle is thin-walled and oblong, forming a pocket-like attachment to the left ventricle. Because of this relationship, contraction of the left ventricle pulls in the right ventricular wall, aiding its contraction. The effect, termed left ventricular aid, explains why some forms of right ventricular failure are less harmful than might be expected. The right and left ventricles are separated by a muscle wall termed the interventricular septum
57.The valve between the right atrium and ventricle is called thetricuspid valve
58.The valves of the heart are flaps of fibrous tissue firmly anchored to theanulus fibrosus cordis (Figure 9-3). Because they are located between the atria and ventricles, they are called atrioventricular valves
59.vasoconstructionconstriction of the smooth muscles in peripheral blood vessels: causes blood pressure to increase even though blood volume is the same
60.vasodilationrelaxation of the smooth muscles in arterioles and causes blood pressure to decrease even though blood volume has not changed
61.venous systemconsists of small expandable venules and veins and larger more elastic veins
62.With 10% blood loss immediate decline in CVP causes…50% decrease in discharge rate of the low pressure atrial baroreceptors


Egan’s Chapter 9 Study Guide:

1. adregeneric stimulation & release of norepinephrine: cause smooth muscle contraction and increase flow resistance


3. anatomic shunt: thebesian veins bypass or shunt around pulmonary circulation.


5. anucleated: have no nucleus (ex:mature RBC’s)

6. Anulus Fibrosus Cordis: AV ring composed of dense tissue, VALVES

7. aortic arch and carotid sinuses: first set of baroreceptors that monitor arterial pressures generated by the left ventricle

8. Arteriovenous asastomosis: DIRECT COMMUNICATION when blood flows between a NETWORK of an ARTERIOLE & through a VENULE

9. automaticity: ability of cardiac muscle to INITIATE a spontaneous electrical impulse

10. baroreceptor output: directly proportional to the stretch on the vessel wall. The greater the BP, greater the stretch, higher the rate of neural discharge to the cardiovascular centers in the medulla

11. baroreceptors: “stretch receptors” respond to pressure changes

12. Basophils: 0-1% differential, have a diameter of 10 nm, have a nucleus contains 3 or 4 lobes, readily absorb stain, contain heparin, prevent coagulation at sites of inflammation

13. blood flow through large veins: affected by abdominal and intrathoracic pressure changes

14. blood functions: transport electrolytes, proteins, water, and hormones; contains platelets and clotting factors for hemostasis

15. blood functions: transports respiratory gases to and from tissue, provides antibodies, carriers nutrients and waste products to cells

16. cardiac output: SV x HR, is equal to circulating blood flow,blood flow per minute, normal range 5L/min, depending on gender, height and weight

17. Cardiac Tamponade: RESULT of Pericardial Effusion, which AFFECTS the PUMPING FUNCTION of the Heart

18. cardiovascular intergrated functions: local and central neural control mechanisms

19. cardiovascular system is responsible: for transporting metabolites to and from tissues; regulates blood flow mainly by altering the capacity of the vasculature and volume of blood it holds

20. causes vasodilation: signals coming from the cerebral cortex in response to exercise, pain, or anxiety, pass directly through the cholinergic fibers to the vascular smooth muscle

21. central controll of blood flow: primarily by the sympathetic division of the autonomic nervous system; skeletol muscle and skin mainly regulated by central control

22. central controls of cardiovascular system: involves both the CNS and circulating humoral agents; maintain a basal level of vascular tone; take over when competing needs of local vascular beds must be coordinated

23. chemoreceptors: respond to changes in blood chemistry

24. chemoreceptors: small, strongly stimulated by decreased O2 tensions, although low pH or high levels of O2 also can increase their discharge rate

25. Chordae Tendineae Cordis: Anchor free ends of AV valves to papillary AV valves to push upwards PREVENTING BACKFLOW

26. Conductance Vessels: Large Arteries in Arterial System. (High elastic & low resistance)

27. conductivity: ability to RADIATE electrical impulses

28. contractility: ability to CONTRACT in response to an electrical impulse

29. Coronary Sinus: Large vessel where VEINS GATHER closely PARALLEL to ARTERIES.

30. decreases in EF: are associated with weakened myocardium or decreased contractility or both; when decreased to 30% or less, a person’s exercise becomes severely limited

31. EDV end-diastolic volume: the amount of blood that fill the ventricles during the resting phase or diastole ranges from 110 to 120 mL

32. EF ejection fraction: percentage proportion of EDV ejected on each stroke is calculated as Ejection Fraction EF = SV divided by EDV EF = SV/EDV

33. Eosinophils: 0-6% differential / have a diameter of 10 nm, have a bilobed nucleus, absorb an acid stain, are present in parasitic and allergic processes

34. erythrocytes: red blood cells, generated in red blood marrow, contain hemoglobin

35. ESV – EDV= SV: approx 2/3 of blood is ejected during systole, EDV ranges from 110 – 120 mL

36. ESV end-systolic volume: small volume remainder of blood in the ventricles during each contraction or systole
part of stroke volume

37. Exchange Vessels: EXCHANGE of NUTRIENTS & WASTE products in the CAPILLARY system

38. excitability: ability to RESPOND to electrical or chemical mechanical stimulation

39. finger pinch check: pinch fingernail until it blanches, checks for cardiovascular integrity

40. finger-puncture / bleeding time: measures amount of time for blood to clot, usually 2-9 minutes

41. Five types of WBC’s: Eosinophils, Monocytes, Lymphocytes, Basophils, Megakaryocyte

42. Fossa Ovalis Cordis: Right side of interatrial septum OVAL DEPRESSION

43. Frank-Starling Law: The more CARDIAC FIBER is STRETCHED the greater the TENSION it GENERATES when CONTRACTED

44. heart plays second role: regulating blood flow; vascular system tells the heart how much blood it needs

45. hematocrit: percentage of RBC’s in whole blood by volume, normally 3 x hemoglobin

46. hematocrit normal ranges: Males 42-54%, Females 38-47%

47. hemocytoblast: common stem cell by process of erythropoiesis

48. hemoglobin: molecule that allows transport of oxygen

49. hypertonic solution of RBC’s: will shrivel (crenation)

50. hypotonic solution of RBC’s: will swell and rupture (hemolysis)

51. hypoxia and acidosis: decrease cardiac contractility and output

52. increases in afterload: can decrease stroke volume

53. indirectly affect HR and vasomotor tone: signals from the hypothalamus through the cardiovascular centers, particularly in its heat-regulating areas

54. left anterior descending artery: anterior wall of both ventricles, anterior wall of ventricle septum

55. left circumflex artery: supplies most blood, posterolateral wall of left vent, anterolateral papillary muscle

56. left coronary artery: left anterior descending artery and circumflex artery

57. Left Coronary Artery (Circumflex Artery): Stronger and has MORE MUSCLE, supplies POSTERIOR side of LEFT VENTRICLE. Supples the most blood.

58. leukocytes or WBC’s: normal value 4500-11,500/mm3 / differential (percentage should add up to 100%) formed in myeloid tissue, perform phagocytosis

59. local controls of cardiovascular system: operate independently, w/o CNS control; alters perfusion under normal conditions to meet metabolic needs;

60. Lymphocytes: 20-45% differential, have a diameter of 6-9 nm, have a round nucleus, cytoplasm appears clear, antibodies that remain infra cellular or form antibodies that are released into bloodstream

61. MAP: normal ranges 80-100 mmHg, directly related to volume of circulating blood and inversely related to it’s capacity; can change resulting from hemorrhagic shock or blood transfusion

62. Megakaryocyte: normal value 150,000-400,000special type of blood cell, thrombocytes or platelets, have a diameter of 2-4 nm, have no nucleus, granular cytoplasm, function in clot formation

63. Monocytes: 2-10% differential / have a diameter of 10-15 nm, have crescent shape nucleus, cytoplasm contains granules, highly phagocytic

64. Myocardial Infarction: COMPLETE OBSTRUCTION may cause TISSUE DEATH or INFARCT

65. myocardial infarction: ischemic tissue distal to clot leads to necrosis, impairs function of ventricles, may lead to lack of blood flow to vital organs

66. myocardial infarction: blockage or impairment flow to coronary arteries, formation of blood clot at site of rupture, plaque on inner wall of coronary artery

67. myocardial infarction risk factors: elevated cholesterol, hypertension, smoking, diabetes, family history

68. myocardial infarction surgical treatment: CABG coronary artery bypass graft, coronary angioplasty, coronary artery stents

69. myocardial infarction treatment: anti-platelet / anticoagulant therapy, clott dissolving drugs, ACE inhibitors, beta blockers, oxygen therapy

70. negative feedback loop: stimulation of a receptor causes an opposite response by the effector.

71. normal ranges of hemoglobin: Males 13.5-16.5 g/dL, Females 12-15 g/dL

72. normal SED rate: Males 0-10, Females 0-20

73. Pericardial Effusion: ABNORMAL amount of FLUID between the LAYERS of the PERICARDIUM


75. plasma: bodies version of water approx 90% of volume; yellow straw like color; whole blood minus cellular component

76. posterior descending artery: area of perfusion: inferior wall of rt ventricle posterior wall of ventricular septum, supplies post intraventricular sulcus

77. Precapillary Sphincters: Capillaries smooth muscle rings at proximal ends. They DECREASE blood flow, CONTROL DIRECTION & AMOUNT of blood flow to an area of a TISSUE

78. Regurgitation: BACKFLOW of BLOOD through an INCOMPETENT or DAMAGED VALVE. (leak in semilunar valves)

79. Resistance Vessels: Arterioles that play a MAJOR ROLE in DISTRIBUTION & REGULATION of BLOOD PRESSURE

80. reticulocytes: RBC’s newly released from marrow that retain small portion of the hemoglobin forming endoplasmic reticulum

81. reticulocytes: normal range 0.5-1.5% percentage of RBC’s that tetIculocytes indicate rate of erythropoioesis

82. reticulocytes: hemoglobin formation complete within 2 or 3 days of release, which is when endoplasmic reticulum disappears

83. right coronary artery: posterior descending artery & rt marginal artery

84. right marginal artery: posteromedial papillary muscles, lateral wall of right ventricle lateral wall of right atrium

85. RT knowledge of chemoreceptors: major cardiovascular effects of chemoreceptor stimulation are vasoconstriction and increased HR

86. SED rate: rate of fall in 1 hour of RBC’s

87. Sliding Filament Theory: Myocardial cells contract when ACTIN & MYOSIN combine to form REVERSIBLE BRIDGES between thick & thin filaments

88. smooth muscle relaxation and dilation: result of stimulation of either cholinergic or specialized beta-adrenergic receptors

89. Stenosis: NARROWING OR CONSTRICTION of a valve outlet

90. stroke volume: is affected by 3 factors: preload, after load, and contractility, volume of blood ejected by the left ventricle during each contraction (systole) normal SV 70mL

91. Thebesian Veins: Coronary VENOUS BLOOD flows back into the heart through thebesian veins. Those ENTERING LEFT SIDE admixture with oxgenated (arterial) blood returning from lungs lower PaO2 level.

92. Thoracic Pump: A mechanism that AIDS VENOUS RETURN. Important to Resp Therapists because Artificial VENTILATION with positive pressure REVERSES NORMAL THORACIC PRESSURE gradients.

93. to avoid organ/tissue damage and to maintain adequate perfusion pressures: the cardiovascular system balances relative volume and resistance

94. total blood volume: 60-80mL/kg of body weight

95. two types of peripheral receptors: baroreceptors & chemoreceptors

96. Venous System: Veins & Venules hold approx. 3/4 total blood volume. Has FOUR mechanisms 1. SYMPATHETIC MUSCLE TONE 2. skeletal muscle pumping “MILKING” 3. CARDIAC SUCTION 4. THORACIC PRESSURE

97. walls of atria & large thoracic pulmonary veins: second set of baroreceptors that respond to changes in vascular volumes through low pressure sensors

98. when a person exercises: skeletal muscle vascular beds dilate, causing large increase in system capacity

99. when blood loss occurs ex:hemorhage: system capacity is decreased by constriction of peripheral vessels

Egan’s Chapter 9 Test Bank:

1. Aortic Valve: a semilunar valve between the left ventricle and the aorta, prevents blood from flowing from the aorta back into the heart

2. Blood flow sequence through vena cave -> aorta: aortic valve, arteries, artierials, capillary, venules,veins, superior and inferior vena cava, right atrium, tricuspid valve, right ventricle, pulmonic valve, pulmonary arteries, pulmonary artierials, capillary, venules, veins, left atrium, mitral valve, left ventricle, aortic valve.

3. calculate cardiac output: HR×SV
EX: 70 beats/min×0.075 L/beat=5.25 L/min

4. calculate ejection fraction & what is normal: EF=SV/EDV
NL 110-120mL

5. controls blood flow into the arteries: small arteries

6. Frank Starling, Law of Heart: The number of cross-bridges is directly proportional to the length of the sarcomere

7. How is mean arterial pressure regulated: by changes in cardiac output and systemic vascular resistance (SVR)

8. low-pressure, low resistance circulatory system: pulmonary system

9. Mitral Valve: A valve in the heart that guards the opening between the left atrium and the left ventricle; prevents the blood in the ventricle from returning to the atrium. Alternative name is bicuspid valve.

10. myocardial tissue: possesses four key properties: Excitability, Inherent rhythmicity, Conductivity,Contractility

11. Pulmonic valve: divides the right ventricular outflow tract from the pulmonary artery. In normal conditions, the pulmonic valve prevents regurgitation of deoxygenated blood from the pulmonary artery back to the right ventricle It is a semilunar valve with 3 cusps, and it is located anterior, superior, and slightly to the left of the aortic valve.

12. tricuspid valve: valve with three cusps,situated between the right atrium and the right ventricle; allows blood to pass from atrium to ventricle and closes to prevent backflow when the ventricle contracts

13. The underlying goal of the bodys cardiovascular control mechanisms: is to ensure that all tissues receive what perfusion according to their metabolic needs

14. What are the heart valves: pulmonic valve, aortic valve, mitral valve, tricuspid valve.

15. What conducts impulses rapidly to ensure synchronous contraction of the ventricules: specialized myocardial tissue such as purkinje

16. what factors determine cardiac stroke volume: preload, afterload, and contractility, heart rate

17. what happens when chemoreceptors are stimulated: vasoconstriction and increased HR

18. which heart chamber has the bulk of muscle mass ?: The two lower heart chambers, or ventricles make up the bulk of muscle mass and do most of the pumping that circulates the blood

19. which part of the nervous system is responsible for the central control of the blood flow: sympathetic division of the autonomic nervous system

Egan’s Chapter 9 Review:

1.13 steps of blood flow through the heart:
–1. R atrium
–2. Tricuspid
–3. R ventricle
–4 Pulmonary valve
–5. Pulmonary trunk
–6. Pulmonary arteries
–7. Lungs
–8. Pulmonary veins
–9. L atrium
–10. Bicuspid/Mitral valve
–11. L ventricle
–12. Aortic valve
–13. Aorta

2. Anatomical structures that make up the fetal circulation: Umbilical vein from placenta to liver, Ductus venous to IVC, Right atrium, Foramen Ovale connect right atrium to left atrium, Ductus arteriosus, Umbilical arteries

3. Aortic valve location: Between LEFT ventricle and aorta

4. Bicuspid/mitral valve location: Between LEFT atrium and LEFT ventricle

5. Cardiac skeleton: – ring of connective tissue that encircles the valves. Electrically isolates the atria from the ventricles

6. Chordae tendonae: Strong fibrous strings that attach cusps of AV valves to heart wall

7. Describe fetal CV circulation: Umbilical vein from placenta to liver, Ductus venosus to IVC, right atrium, Foramen Ovale(bypass) connects right atrium to left atrium, Ductus arteriosus, Umbilical arteries (2)

8. Describe post-natal CV circulation: Occlusion of placental flow causes pressure drop in IVC and right atrium, Aeration of lungs results in increased pulmonary flow, increased flow raises pressure in left atrium, also closure of umbilical arteries increases systemic pressure, Pressure gradient closes foramen ovale

9. Describe the average person’s heart: Cone shaped muscle; fist size

10. Describe the fibrous pericardium: Attached to the great vessels and the diaphragm. It is a tough, inelastic connective tissue.

11. Describe the physiological processes that can result from mitral regurgitation: Left ventricle works harder than left atrium. Heart murmurs.

12. Describe the physiological processes that can result from mitral stenosis: Left atrium works harder than left ventricle. Blood begins to back up, More energy is expended with less positive results, Heart murmurs.

13. Describe the serous pericardium: A delicate double layer of serous membrane. Parietal pericardium lines the inside of the fibrous pericardium. Visceral pericardium – covers the surface of the heart. Pericardial cavity is the space between the parietal and
visceral pericardium.

14. Describe the two atria: Right atrium receives deoxygenated blood from body tissues. Left atrium receives oxygenated blood from lungs

15. Describe the two ventricle: Right ventricle pumps blood to the lungs. Left ventricle pumps blood to the body tissues

16. Endocardium: Inner layer of epithelium and connective tissue

17. Epicardium: The outer covering of the heart (AKA visceral pericardium)

18. Fossa ovalis: A depression in the interatrial septum that is the residual of the foramen ovale of the fetal circulation

19. Four chambers of the heart: Left atrium, Left ventricle, Right atrium, Right ventricle

20. The four valves found in the heart: Bicuspid/mitral (AV), Tricuspid (AV), Aortic (semilunar), Pulmonary (semilunar)

21. The functions of all valves in the heart: To keep blood flowing in one direction. To make the heart more efficient and use less energy

22. The leading cause of death in the US: Cardiovascular Disease (2600 people die each day, 2x more than cancer)

23. List the mechanisms responsible for the changes that occur in the transition from fetal to postnatal circulation: Pressure and chemical changes due to increased alveolar pressure lead to anatomical and physiological changes in the circulatory system

24. Long term volume maintenance is based primarily on what?: Low pressure baroreceptors in atria and large thoracic veins

25. The most common CVD: Coronary Artery Disease

26. Mycardium: Middle layer – cardiac muscle tissue

27. Potential events if inadequate perfusion of tissue occurs: Less than peak performance. Inability to heal. If stressed long enough, it will die

28. Pulmonary valve location: Between RIGHT ventricle and pulmonary trunk

29. The purpose of semilunar valves: To assure that blood flows in one direction from the ventricles to the large arteries they connect to

30. The purpose of the AV valves: To assure that blood flows in one direction from the atrium to the ventricle

31. Regurgitation: Valve fails to close completely and allows backflow

32. Risk factors for CVD:
– Genetics (#1)
– Hypertension (HTN)
– Elevated cholesterol
– Diabetes (esp. Type II)
– Obesity
– Smoking
– Inactivity
– Gender (women are catching up to men)

33. Stenosis: Narrowing of aperture (partial obstruction)

34. Three layers of the pericardium: Fibrous, Perietal, Visceral

35. Three walls of the heart: Epicardium, Myocardium, Endocardium

36. Tricuspid valve location: Between RIGHT atrium and RIGHT ventricle

37. The two atrioventricular valves: Bicuspid (or mitral), Tricuspid.

38. The two semilunar valves: Aortic, Pulmonary

39. The two septum found in the postnatal heart: …

40. The ultimate function of the cardiovascular system: To ensure that all tissues are adequately perfused

41. What borders the heart in the mediastinum?: Lungs, vertebrae, and sternum

42. What is the difference between the visceral pericardium and the epicardium?: Location

43. What is the first functional organ?: The heart (day 22)

44. What is the purpose of the fluid in the percardial cavity?: Lubricate and reduce energy demands

45. What separates the two atria?: The interatrial septum

46. What separates the two ventricle?: The interventricular septum

47. When does a fetus secrete sufficient surfactant?: 25-28 weeks

48. When does surfactant secretion begin?: 24 weeks

49. When do the lungs begin to develop?: 6 weeks

50. When do the lungs begin to function?: At birth

51. When is a fetus potentially viable?: 24-26 weeks

52. Where is the apex of the heart?: At the 5th intercostal space

53. Where is the base of the heart?: At the 2nd rib

54. Which are the pumping chambers?: The ventricle

55. Which are the receiving chambers?: The atria

56. Why does a fetus need a different CV system than before birth?: Because the lungs do not function.