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Cardiac Pathologies > CARDIAC ANATOMY > Flashcards

CARDIAC ANATOMY Flashcards

1
Q

Where is the septo marginal trabecula located?

A

Right ventricle

The “moderator band” is important because it carries part of the right bundle branch of the AV bundle of the conduction system of the heart to the anterior papillary muscle. This shortcut across the chamber of the ventricle seems to facilitate conduction time, allowing coordinated contraction of the anterior papillary muscle.

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2
Q

What are the contents of the middle mediastinum?

A
  1. Heart
  2. Great blood vessels
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3
Q

Why can the mediastinum accommodate movement and volume changes?

A

due to the looseness of the connective tissue, combined with the elasticity of the lungs and pleura

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4
Q

What does the pericardium enclose?

A

heart and roots of great vessels

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5
Q

Layers of the pericardium:

A
  1. Outer fibrous layer (fibrous pericardium)
  2. Inner double layered sac (serous pericardium):
    • Parietal pericardium (outer layer)
    • Visceral pericardium (inside layer) AKA epicardium
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6
Q

Outer fibrous layer of the pericardium attaches to:

A
  • Outer layer of the great vessels
  • Central tendon of the diaphragm
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7
Q

Function and contents of the pericardial cavity:

A
  • Contains a thin layer of serous fluid.
  • Allows the heart to beat in a frictionless environment
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8
Q

Innervation of the parietal pericardium:

A

phrenic nerve

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9
Q

innervation of the visceral pericardium

A

no innervation, insensitive to pain

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10
Q

Inflammation of the pericardium:
presentation?

A
  • Pericarditis
  • Presents as substernal pain and can result in pericardial effusion
  • Pericardial rub (auscultation)
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11
Q

Location of the heart

A

2/3 to the left of the median plane
within the pericardial sac

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12
Q

Where is the apex of the heart found?

A
  • Most inferior portion of the heart
  • 5th intercostal space
  • midclavicular line in supine
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13
Q

where is the point of maximun impulse located?

A

in the apex of the heart

(5th intercostal space)

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14
Q

what is the point of maximal impulse?

A

Apex of the heart, is where the cardiac impulse can be best palpated on the chest wall. Frequently, this is at the 5th intercostal space

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15
Q

What structure of the heart forms the apex?

A

tip of the left ventricle

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16
Q

What structure of the heart forms the base?

A

2 atria

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17
Q

where is the base of the heart located?

A
  • The most superior portion of the heart
  • 2nd intercostal space
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18
Q

Aorta and pulmonary trunk exit and the superior vena cava enters the heart here:

A

Base of the heart (most superior portion)
2nd intercostal space

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19
Q

layers of the heart

A
  1. Epicardium AKA visceral pericardium
  2. Myocardium
  3. Endocardium
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20
Q

What is the shape of the R and L ventricles?

A
  • R ventricle = crescent shaped
  • L ventricle = conical in shape
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21
Q

Myocardial cells are grouped in to 2 structural categories:

A
  1. Mechanical cells (myocytes)
  2. Conductive cells
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22
Q

The metabolic processes of the myocardium are almost exclusively…

A

aerobic​

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23
Q

Intercalated disks join myocytes (mechanical cells) together to form a

A

syncytium

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24
Q

what make up the 2 syncytiums of the heart?

A

the atria and ventricles

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25
Q

4 Properties of myocardial cells:

A
  • Automaticity: Ability to initiate own depolarization, to contract in the absence of stimuli, w/o direct
    stimulation needed from a nerve
  • Rhythmicity: Ability to contract in a regular, rhythmic manner
  • Conductivity: Ability to spread impulses to adjoining cells quickly
  • Excitability: The cells transmit nerve impulses
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26
Q

Can myocardial cells replace injured cells?

A

NO

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27
Q

receives blood from the veins of the heart and delivers it to the right atrium

A

Coronary sinus

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28
Q

where is the coronary sinus located?

A

Coronary sulcus or groove (aka: atrioventricular sulcus/groove)

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29
Q

what is in the coronary sulcus?

A

the coronary sinus

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30
Q

what runs over the anterior interventricular sulcus?

A

blood vessels and fat

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31
Q

what is the cardiac skeleton made of?

A

anulus fibrosus (fibrocartilaginous tissue)

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32
Q

what is the function of the anulus fibrosus?

A
  • Separates the atria from the ventricles
  • Acts as electrical insulator between atria and ventricles so impulses only move through the AV node
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33
Q

what acts as electrical insulator between atria and ventricles so impulses only move through the AV node?

A

anulus fibrosus

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34
Q

5 types of WBC:

A
  • neutrophils
  • eosinophils
  • basophils
  • monocytes
  • lymphocytes
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35
Q

leukocytes AKA

A

WBC

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36
Q

erythrocytes AKA

A

Red blood cells (RBC)

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37
Q

What is the plasma of the blood made of?

A
  • Suspends RBC, WBC, and platelets
  • Has gases, salts, carbohydrates, proteins, and lipids
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38
Q

Pulmonary arterial pressure is ______ that of systemic pressures

A

1/6th

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39
Q

Where is the SA node located?

A

Right atrium

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40
Q

what is the fossa ovale and where is it located?

A
  • On the right atrium
  • During fetal development, the foramen ovale allows blood to pass from the right atrium to the left atrium, bypassing the nonfunctional fetal lungs while the fetus obtains its oxygen from the placenta.
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41
Q

what is the main concern with atrial septal defect

A

can overflow the pulmonary system

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42
Q

Normal filling pressure of the right atrium AKA central venous pressure (CVP)

A

0 - 8 mmHg

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43
Q

Parallel muscle bundles that compose the inner wall of the right atrium – “comb like”

A

pectinate muscles

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44
Q

true or false: orthotopic heart transplants usually involve the excision of the RA (LA and great vessels are left in place) and the donor’s heart is then attached to the RA

A

true

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45
Q

right atrioventricular valve AKA

composed of:

A
  • TRICUSPID VALVE
  • Composed of 3 cusps/leaflets: anterior, posterior and septal (medial)
    • These are thinner than those of the mitral valve
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46
Q

AV valves system of structures:

A
  • from the wall of ventricle:
  1. Trabeculae carneae (aka: Rathke’s bundles)
  2. Papillary muscles
  3. Chordae tendineae
  4. Valve leaflets/cusps
  5. Valvular orifice surrounded by an annulus
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47
Q

Normal systolic pressure in the right ventricle = ?

End diastolic pressure = ?

A
  • right ventricle = 15-28 mm Hg
  • 0-8 mm Hg
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48
Q

which is the thickest layer in the veins?
How about in the arteries?

A
  • Veins: tunica adventitia or externa
  • Arteries: tunica media
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49
Q

In the right ventricle, resistance of pulmonary circulation is about ____ that of systemic circulation

A

1/10th

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50
Q

the right ventricle generates less than ____ the stroke work of the left ventricle

A

¼

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51
Q

right semilunar valve AKA

A

PULMONARY VALVE

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52
Q

left semilunar valve AKA

A

AORTIC VALVE

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53
Q

how many leaflets/cusps do the semilunar valves have?

A

3

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54
Q

true or false, semilunar valves open and close solely based on pressure gradient changes in the heart during the cardiac cycle

A

true

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55
Q

what is the location of the right semilunar valve?

A

3rd costal cartilage to the left of the sternum

(AKA pulmonary valve)

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56
Q

Contraction of the right ventricle pushes blood through the ________ into the pulmonary trunk

A

pulmonary valve

or right semilunar valve

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57
Q

the left atrium collects blood from where?

A

the right and left pulmonary veins
oxygenated blood

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58
Q

What represents the original heart tube and serves no function

A

Auricular appendage (or “dog ear”)

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59
Q

Blood flows through the left ______ into the left ventricle

A

AV orifice (mitral valve)

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60
Q

what is the normal filling pressure of the left atrium?

A

4-12 mm Hg

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61
Q

Forms most of the posterior surface of the heart

A

left atrium

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62
Q

Collects blood from right and left pulmonary veins:
– Carry oxygenated blood from the lungs

A

left atrium

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63
Q

Walls of the left atrium are slightly thicker than right atrium, why?

A

the left atrium does more work against the resistance of the sistemic circulation

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64
Q

In certain cardiac conditions (ex:
atrial fibrillation) a ________ can form on the wall of the left atrium and if it breaks off, it can travel to and occlude peripheral arteries (an occlusion of the artery of the brain can result in a stroke)

A

thrombus

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65
Q

Mitral Valve AKA

A

Left AV Valve

AKA bicuspid valve

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66
Q

what guards the opening between the left atrium and the left ventricle

A

mitral valve AKA left AV valve AKA bicuspid valve

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67
Q

the physician is listening with the stethoscope situated in 5th intercostal space and midline of the clavicle:

A

Mitral valve AKA bicuspid valve

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68
Q

where is the mitral valve (bicuspid valve) located?

A

Situated posterior to sternum at level of 4th left costal cartilage

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69
Q

which is the most frequently diseased valve in the heart?

A

Mitral Valve

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70
Q

what is Mitral Valve Insufficiency?

A
  • Mitral insufficiency (MI), mitral regurgitation or mitral incompetence is a disorder of the heart in which the mitral valve does not close properly when the heart pumps out blood.
  • It is the abnormal leaking of blood backwards from the left ventricle, through the mitral valve, into the left atrium, when the left ventricle contracts, i.e. there is regurgitation of blood back into the left atrium.
  • MI is the most common form of valvular heart disease
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71
Q

Mitral Valve Prolapse:

A

displacement of an abnormally thickened mitral valve leaflet into the left atrium during systole

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72
Q

Mitral Stenosis

A

narrowing of the orifice of the mitral valve of the heart.

73
Q

The left ventricle receives blood from left atrium via mitral valve and pumps blood into ______ via ________ .

A

aorta (and systemic circulation) via aortic valve

74
Q

Makes up nearly entire left border and surface of the heart – “inferior wall”

A

Left Ventricle

75
Q

The left ventricle has a thick muscular wall that is ____ times as thick as the right ventricular wall

A

2-3

76
Q

Superior and anterior portion of the left ventricle is formed by the…

A

aortic vestibule

(is the entry way bellow the mitral valve)

77
Q

in the left ventricle, 2 large papillary muscles give rise to _____ ________ which attach to the cusps of the mitral valve

A

chordae tendinae

78
Q

Normal systolic and end-diastolic pressure of the left ventricle:

A
  • systolic = 90-140 mmHg
  • end-diastolic = 4-12 mmHg
79
Q

Wall which partitions right and left ventricles and composed of muscular and membranous portions

A

Ventricular Septum

AKA: Interventricular Septum

80
Q

does the interventricular septum contain electrical conduction tissue?

A

yes

81
Q

functions of the ventricular sptum:

A
  • Contains electrical conduction tissue
  • Provides stability to the ventricles during contraction
82
Q

Margins of the ventricular septum correspond with the…

A

anterior and posterior interventricular grooves

83
Q

where is the aortic valve located?

A

2nd right intercostal space at the sternal border

84
Q

Contraction of the left ventricle pushes blood through the _____ into the aorta

A

aortic valve

85
Q

Guards the aortic orifice

A

Aortic Valve

86
Q

The Great Vessels “Primary Blood Vessels”:

A
  • Vena Cava: sup and inf
  • Pulmonary veins: 4, two from each lung
  • Pulmonary arteries: one to each lung
  • Aorta
87
Q

blood vessels have three layers of tissue called:

A

TUNICS

  1. Tunica Intima: innermost layer
  2. Tunica Media: mainly smooth muscle
    • Makes up the bulk of the arterial wall
  3. Tunica Adventitia or Externa: contains both elastic and collagenous fibers
    • Thickest layer in veins
88
Q

Types of arteries:

A
  • Elastic (closer to the heart)
  • Muscular (maintain BP)
  • Arteriole (peripheral resistance, capillaries)
89
Q

connections between arterial branches providing collateral circulation to capillary beds

A

anastomoses

90
Q

Which arteries deliver deoxygenated blood?

A

the pulmonary and umbilical arteries

91
Q

which blood vessel create anastomoses more easily?

A

VEINS create anastomoses more easily than arteries

92
Q

types of veins:

A

– Venule
– Medium size
– Larger

93
Q

Vein rely on a system of ____ and muscular contraction to ensure blood flow back to the heart

A

valves

94
Q

Oxygen, CO2, nutrients, and wastes are exchanged through their thin walls

A

capillaries

95
Q

what connects arterioles to venules?

A

capillaries

96
Q

Capillary walls are thin and composed of ________

A

endothelium

97
Q

Lymphatic contain ____ to ensure one way flow to the heart

A

valves

98
Q

3 branches from of the aortic arch

A
  1. Brachiocephalic or Innominate
  2. L Carotid
  3. L Subclavian
99
Q

Parts of the aorta

A
  • Ascending
  • Aortic arch
  • Descending:
    • Thoracic aorta
    • Abdominal aorta
100
Q

Descending aorta, divides into:

A
  • Thoracic aorta
  • Abdominal aorta
101
Q

This is one of the anatomic dilations of the ascending aorta, which occurs just above the aortic valve. These widenings are between the wall of the aorta and each of the three cusps of the aortic valve

A

AORTIC SINUS AKA Sinus of Valsava

102
Q

Sinus of Valsalva

A

An anatomic dilation of the ascending aorta

103
Q

*

what give rise to the right and left coronary arteries

A

Right and left sinus areas

104
Q

Right atrium receives blood from the _____

A

systemic circulation

105
Q

Right atrium contracts and
pushes blood through the ___________ → __________

A

tricuspid → R ventricle

106
Q

when does the tricuspid valve close

A

when the right ventricle contracts (ventricular systole)

107
Q

circulation of the right side of the heart

A

systemic circulation → right atrium → tricuspid valve → right ventricle → pulmonary valve → pulmonary trunk → pulmonary arteries → lungs

108
Q

circulation of the left side of the heart

A

4 pulmonary veins → left atrium → mitral valve → L ventricle → aortic valve → systemic circulation

109
Q

when does the mitral valve close?

A

when the L ventricle contract to prevent backflow into the left atrium

110
Q

Blood is supplied to the muscle of the heart via

A

right and left coronary arteries

111
Q

what is the crux of the heart?

A

where the atrioventricular and interventricular grooves meet at the posterior aspect of the heart

112
Q

Right or left coronary dominance is determined by

A

which artery crosses the crux and supplies the AV node

113
Q

coronary arteries travel around the heart in which structures?

A
  • 2 grooves:
    • Atrioventricular groove (aka coronary sulcus)
    • Interventricular groove
114
Q

Coronary arteries give rise to_______ arteries that travel deep into the myocardium

A

perforating​

115
Q

Capillary network of the heart is about _____ for each muscle cell

A

1 capillary

116
Q

Which artery supplies the SA and AV nodes?

A

Right coronary artery

117
Q

Which artery supplies blood to left atria and most of the left ventricle, parts of the right ventricle as well as the interventricular septum

A

Left Coronary Artery (LCA)

118
Q

Left coronary artery (or Left Main) divides into 2 main branches

A
  • Left Anterior Descending (LAD) or Anterior Interventricular Artery (“widow maker”)
  • Left Circumflex (LCX)
119
Q

which artery travels in the anterior interventricular groove

A

Left Coronary Artery (LCA)

120
Q

the LCA Anastomoses with the posterior branches of the

A

RCA

121
Q

Left coronary artery supplies blood to:

A
  • Anterior two-thirds and posterior parts of the interventricular septum
  • Most of L ventricle, L atrium
  • Parts of the R ventricle
122
Q

which is the most commonly occluded coronary artery

A

Left Anterior Descending“widow maker”

(a branch of the Left Coronary Artery)

123
Q

which artery supplies most of the left atrium and the posterior and lateral walls of the left ventricle

A

left circumflex, a branch of the LCA

124
Q

which artery supplies blood to the right atrium, right ventricle, interventricular septum, and inferior wall of the left ventricle

A

Right Coronary Artery

125
Q

Terminal portion of the _____ descends towards the apex of the heart

A

RCA

126
Q

Which artery supplies the SA and AV node?

A

Right Coronary Artery

  • SA Nodal Artery: branches off of the RCA at the crux of the heart to pass anteriorly along base of atrial septum to supply to AV node
    • Occurs in ~55% of hearts
    • In the other 45% it comes from a branch of the LCX
  • AV Nodal Artery: usually branches off of the distal RCA
    • Occurs in ~85-90% of hearts
    • In the other 10-15% it comes from a branch of the LCX
127
Q

which is the main vein of the heart?

A

Coronary sinus

128
Q

where is the coronary sinus located?

A

Located in the posterior portion of the coronary groove on the posterior surface of the heart

129
Q

where does the coronary sinus empty its blood?

A

directly into the right atrium

130
Q

the coronary sinus receives drainage from:

A
  • Great cardiac vein
  • Middle cardiac vein
  • Small cardiac vein
    • Thebesian veins are the smallest of the cardiac veins
131
Q

which are the smallest of the cardiac veins?

A

Thebesian veins

132
Q

Function of the heart and cardiovascular system

A
  • Deliver O2 and nutrients to all tissues in the body and remove CO2 and waste products, via the blood
  • Transport of heat to maintain body temp
  • Transport of WBCs to fight infection
  • Transport of hormones
133
Q

Heart muscle cells called _________ are polarized, negatively charged, at rest

A

myocytes

What happens when myocytes become positive?

134
Q

repolarization of myocytes (phase 3) =

A

relaxation

135
Q

Depolarization of myocytes (phase 2)

A
  • When the myocytes become positive they contract
  • Move as a wave through the myocardium
136
Q

Recovery phase following depolarization is called what?

A

Repolarization (relaxation)

Return to resting negative charge (phase 1)

137
Q

Records the electrical activity of the heart and give information about heart’s function and structure

A

Electrocardiogram (EKG)

138
Q

P wave, QRS, and T wave

A
  • P wave – atrial depolarization
  • QRS – ventricle depolarization
  • T wave – ventricular repolarization
139
Q

Conduction System of Heart

A
  1. Sinoatrial (SA) Node
  2. Internodal Conduction Pathways
  3. Atrioventricular (AV) node
  4. Bundle of His
  5. Bundle branche
  6. Purkinje fibers
140
Q

what is the sinus rhythm?

A
  • Sinoatrial (SA) NODE
  • “Pacemaker of the heart” (normally) with the innate rate of impulse generation of 60-100 bpm
141
Q

Where is the SA node located?

A

Located at the junction of the superior vena cava and the RA

142
Q

The action potential travel from SA node to AV node via

A

internodal tracts

143
Q

Initiate the cardiac cycle

A

Sinoatrial (SA) NODE

144
Q

LCA supplies blood to

A
  • Left atrium
  • Left ventricle
  • Parts of R ventricle
  • Interventricular septum
145
Q

RCA supplies blood to:

A
  • R atrium
  • R ventricle
  • Apex of the heart
  • Interventricular septum
  • SA and AV node
146
Q

Stroke volume is affected by

A
  • Preload (compliance vs non compliance)
  • Contractility (HR > 120 bpm)
  • Afterload: (total peripheral resistance: Resistance increases → force of contraction
    decreases ➔SV decreases)
147
Q

AV node is located in the …

A

right atrial septal wall near the tricuspid valve

148
Q

The AV node receives the electrical impulses originated at the SA node and conducts it to the

A

Bundle of His

149
Q

In a normal heart the only way that the electrical impulse can spread from the atria to the ventricles is via the

A

AV node

150
Q

innate rate of impulse generation of the SA node:

A

60-100 bpm

(sinus rhythm)

151
Q

Inherent rate of the AV node:

A

40-60 bpm

152
Q

2 functions of AV NODE:

A
  1. When impulse arrives at AV Node depolarization slows causing a delay of .04 sec to allow the ventricles to fill with blood from the atria—“atrial kick”
  2. Controls the number of impulses going to the ventricles
153
Q

Bundle of His:

A
  • The cardiac impulse travels from the AV Node to the Bundle of His where it divides into right and left bundle branches, and terminates into Purkinje fibers:
    • Continuous with cardiac muscle in the ventricles
    • Stimulate ventricular contraction​
  • Inherent firing rate of 20 to 40 bpm
154
Q

Myocardial infarction in the interventricular septum may result in a

A

“bundle branch block”

155
Q

Heart Rate “pacemaker” summary:
SA, AV, an Purkinje fibers rhythm

A
  • SA Node “pacemaker” = 60 - 100 bpm
  • AV Node = 40 - 60 bpm
  • Purkinje Fibers = 20 - 40 bpm
156
Q

true or false: chambers of the heart are isolated both electrically and physically

A

true

157
Q

The heart is controlled by 2 opposing divisions of the autonomic nervous system (ANS):

A
  • SYMPATHETIC NERVOUS SYSTEM:
    • Dominates during stressful situations →leading to tachycardia, increased cardiac output (CO) and increased O2 demand
    • “adrenergic” nerve cells of ANS that use norepinephrine as neurotransmitter
  • PARASYMPATHETIC NERVOUS SYSTEM:
    • Dominates during relaxed states → leading to resting HR, baseline CO, and decreased O2 demand of the heart
    • Controls heart through the vagus nerve (CN X) and the release of acetylcholine (vagus nerve)
    • “cholinergic”
158
Q

What does the cardiac plexus consist of?

A

sympathetic and parasympathetic nerves

Serves as a conduit for neurotransmitters (ex: norepinephrine and acetylcholine) to reach target receptors in the heart

159
Q

sympathetic and parasympathetic nerve supply to the heart:

A
  • Sympathetic (adrenergic):
    • Monitors SA, AV node
    • Accelerates cardiac activity
  • Parasympathetic (cholinergic):
    • ​​Also monitors SA node
    • Slows cardiac activity
160
Q

“Vaso-vagal event”

A

Syncope or fainting due to a trigger that increases vagal tone leading to decrease in HR and BP

161
Q

Bainbridge Reflex

A

Stimulation of stretch receptors in the right side of the heart by increased venous return → increases the heart rate

162
Q

The Bainbridge reflex, also called the atrial reflex, is an increase in

A

heart rate due to an increase in central venous pressure

163
Q

Increased arterial blood pressure stimulates nerve endings in the carotid sinus and aortic arch → and will…

A

reduces the heart rate.

164
Q

Baroreceptors sense changes in BP and “report” abnormal BP to the CNS →

A
  • High BP or arterial baroreceptors respond to high BP very quickly by lowering rate and blood vessel resistance (dilate)
  • Low pressure baroreceptors regulate blood volume in the body
165
Q

Chemoreceptors function:

A
  • detect levels of oxygen, pH and carbon dioxide in the blood to determine when someone needs to increase HR or RR
166
Q

Cardiac Cycle — 5 Phases

A
  • Mid Diastole: 80% of blood to ventricles; AV valves are open
  • Late Diastole: remaining 20% of volume comes into ventricles; “atrial kick”; SA node has fired
  • Early Systole: Impulse through AV Node → Ventricles; AV valves close, S1 Lub sound; Isovolumetric contraction
  • Late Systole: Ventricular ejection (rapid); ejection fraction; end systolic volume
  • Early Diastole: S2 DUB sound, pulmonic and aortic valves are shut; repolarization occurs; Isovolumetric relaxation

Each cycle lasts ~0.8 sec

167
Q

S1 LUB sound occurs during

A

Early Systole

  • AV valves close
  • Isovolumetric contraction
168
Q

S2 DUB sound occurs during

A

Early Diastole

Pulmonic and aortic valves close

169
Q

Repolarization occurs during

A

Early Diastole

170
Q

Resistance increases → force of contraction ________

A

decreases ➔ SV decreases

171
Q

which artery supplies the bundles of Hi

A

Left Coronary Artery

172
Q

Frank-Starling Mechanism:

A

the greater the volume in the ventricle → the greater the contractile strength of the ventricles

Because the myocardium will become more stretched → will increase sarcomere length and increase sensitivity to calcium ions → therefore, stronger contraction

173
Q

afterload is dependent on:

A
  • Volume and mass of blood ejected
  • Size and wall thickness of ventricle
  • Impedance of vasculature

(afterload is The resistance, impedance, pressure that the ventricle works against to eject blood)

174
Q

afterload, as resistance increases force of contraction….

A

decreases → SV decreases

175
Q

Pressure in LV before it contracts

A

Preload

176
Q

LV End Diastolic Pressure

A

preload:

  • Amount of muscle fiber stretch at end of diastole
  • Amount of volume in the ventricle at this phase
  • “pulling back the rubber band”
177
Q

preload

A
178
Q

Capillaries exchange ______(4 things)______ through their thin walls

A

Oxygen, CO2, nutrients, and wastes

Cardiac Pathologies (13 decks)

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