S2 - Heart: Embryology, Thoracic Cage, Anatomy Flashcards

1
Q

4 main stages of the embryonic period

A
  • cleavage, implantation, gastrulation (tri laminar disc)
  • embryonic (organs develop, heart and limbs complete)
  • foetal period (organs become more mature)
  • post-birth (CNS, lungs still developing)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

describe foetal circulation including shunting

A
  • umbilical vein carries oxygenated blood (from placenta) to liver
  • h/w liver not functioning yet so need to shunt/bypass - ductus venosus
  • blood reaches R atrium > would normally go to lungs h/w lungs don’t work so need to shunt again - ductus arteriosus (from pulmonary trunk to aorta)
  • OR thru foramen ovale (connects atria to allow blood to go from RA > LA > LV > aorta > body)
  • blood distributed to head then rest of body (shows that brain develops earlier than rest of body)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

describe pressure in the heart (foetal vs adult)

A
  • foetal: high on R side b/c lungs don’t function (helps to shunt blood to the L side) - lungs receive little blood to help them develop but not a lot
  • adult: high on L side b/c lungs work and the L side pumps to the rest of the body
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

which adult structures are formed by the 3 foetal shunts

A
  • ductus venosus (liver) - forms ligamentum venosum
  • foramen ovale (atria) - forms fossa ovalis
  • ductus arteriosus (between PT and aorta) - forms ligamentum arteriosum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

2 functions of a DEVELOPING heart

A
  • support foetal circulation
  • prepare to support circulation after birth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

which embryonic layer becomes the heart?

A
  • mesoderm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

general formation process of the heart

A
  • formation of a single cardiac tube which starts beating
  • heart loops around
  • septa form (atrial and ventricular)
  • valves from
  • outflow tract (truncus arteriosus) partitions into pulmonary trunk + aorta
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

describe how the heart moves from the cervical region to the thoracic cavity

A
  • cranial-caudal folding
  • brain grows very quickly > causes forward tilt > foetal position
  • middle region contains rigid somites which don’t move > flat region
  • tail curls
  • forces heart and diaphragm into thorax
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

which embryological structure gives rise to the diaphragm?

A
  • septum transversum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

which type of folding results in a single heart tube?

A
  • lateral folding: 2 tubes merge into 1
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

describe anatomical indications of the heart’s relationship w/ the diaphragm and liver

A
  • pericardium and liver attached to diaphragm
  • diaphragm innervated by C3-5 (phrenic n.) = must have dragged down cervical nerve roots when it moved from cervical region > thorax
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what are A, B, C?

A
  • A = outflow tract (truncus arteriosus)
  • B = bulbus cordis
  • C = primitive ventricle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are D, E, F?

A
  • D = primitive atria: forms muscles in atria
  • E = sinus venosus > forms smooth walls of atria
  • F = inflow
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

describe how the single heart tube moves into different positioning

A
  • outflow was superior > moves anterior and inferior (ventricles)
  • inflow was inferior > moves more posterior and superior (atria)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what are the endocardial cushions?

A
  • located in the middle of the heart (dorsal and ventral)
  • gives signals for heart septation and valve formation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

describe the process of atrial septation

A
  • 1) septum primum grows b/n atria
  • 2) foramen primum grows in septum primum
  • 3) septum primum reaches endocardial cushion > closes off foramen primum
  • 4) ostium (foramen) secundum forms (superior to primum)
  • 5) septum secundum forms to the right of primum - thicker wall, rigid
  • 6) foramen ovale forms (inferior to ostium secundum)
  • 7) FINALLY - when blood flows from R > L, it opens the flexible septum primum. As pressure gets higher on the L side, it closes. this should actually fuse a few weeks after birth, but in some ppl does not close > ‘probe patent’
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what is the septum secundum defect?

A
  • when foramen ovale or foramen secundum are too large and overlap
  • doesn’t close after birth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

atrial septal defect - probe patent fossa ovalis

A
  • when the septum primum does not fuse into the septum secundum
  • may never lead to any Sx b/c pressure is high on L side so keeps septum secundum closed
  • becomes an issue during pulmonary stenosis > increased pressure on R side which opens the foramen ovale
  • mixing of oxygenated and deoxygenated blood
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

ventricular septation

A
  • septum simply grows towards endocardial cushion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

how are the papillary muscles formed?

A
  • from heart tissue itself
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

ventricular septal defect
- is this harmful in a foetus?

A
  • when ventricular septum doesn’t form properly
  • not harmful in utero b/c pressure is higher on R side so shunting occurs anyway
  • when born: pressure increases on L side = mixing of blood
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

endocardial cushion defect and is this an issue in a foetus?

A
  • ECC doesn’t grow properly > atrial and ventricular septa dont develop
  • mixing of blood in all 4 chambers
  • not an issue in FOETUS b/c they get their oxygenation from mother
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

describe what happens during outflow septation

A
  • truncus arteriosus splits into aorta and pulmonary trunk ( > 2 pulmonary arteries), which twist around
  • from regular anatomical view: aorta is posterior and right
  • pulmonary trunk is anterior and left
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

describe the semilunar valve structure

A
  • aortic valve: posterior cusp
  • pulmonary trunk valve: anterior cusp
  • both still have a R and L cusp but kinda twisted
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

how to tell L and R side of heart

A
  • use coronary arteries: the LCA one splits into 2 (LAD and circumflex), the RCA is just one
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

auscultation position for 4 heart valves

A
  • pulmonary and aortic valves are right behind the sternum so not useful
  • All Patients Take Medicine
  • aortic valve: 2nd R parasternal
  • pulmonary valve: 2nd L parasternal
  • tricuspid: 4th L parasternal
  • mitral: 5th L midclavicular
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

describe where the recurrent laryngeal nerves run

A
  • vagus nerve gives off L and R recurrent laryngeal nerves
  • R: hooks around subclavian artery
  • L: hooks under arch of aorta
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

what happens when the truncus arteriosus doesn’t develop properly?

A
  • persistent truncus arteriosus: aorta and PT don’t divide > mixing of blood
  • transposition of great vessels: linear formation instead of twisting > each vessel comes out of the wrong ventricle
  • due to endocardial cushion defect
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

treatment for transposition of great vessels

A
  • give prostaglandins to maintain ductus arteriosus
  • since pressure is higher on L side than R side, this will force blood the other way thru the right vessel
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

which conditions will lead to cyanosis?

A
  • basically anything that involves deoxygenated blood entering systemic circuit
  • tetralogy of fallot (pulmonary stenosis, VSD, overriding aorta, R ventricular hypertrophy) - these don’t cause cyanosis on their own, but because of the overriding aorta sitting over the VSD, mixed blood enters systemic circuit
  • transposition of great vessels
  • persistent truncus arteriosus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

which conditions will not lead to cyanosis?

A
  • conditions where oxygenated blood still reaches systemic circuit
  • ASD, VSD
  • patent ductus arteriosus
  • aortic or pulmonary stenosis, aortic coarctation (narrowing), mitral stenosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

functions of the thoracic cage

A
  • protect organs from injury
  • aids in respiration by providing space, decreasing friction and coordinating movement
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

components of the thoracic cage

A
  • ribs
  • vertebra
  • sternum
  • intercostal muscles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

what are A, B, C, D, E?

A
  • A = clavicles
  • B = suprasternal/jugular notch
  • C = xiphisternal junction
  • D = sternal angle/ angle of Louis
  • E = costal margin and xiphoid process
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

what are A, B, C, D, E?

A
  • A = level of nipple shows 4th intercostal space (ideally)
  • B = anterior median line
  • C = parasternal lines
  • D = midclavicular lines
  • E = mammillary lines
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

why is the nipple a bad surface landmark for a physical exam?

A
  • its position can vary a lot based on breast size, pregnancy, gender etc
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

what are A, B, C?

A
  • A = anterior axillary line
  • B = mid axillary line
  • C = posterior axillary line
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

what is the thorax directly connected to and what is the significance of this?

A
  • head and neck
  • upper limbs
  • abdomen
  • therefore chest pain can be referred from any of these regions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

why is the diaphragm innervated by the phrenic nerve?

A
  • originated in cervical region and migrated down into thorax
  • therefore brought down C3-C5 with it
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

why do newborns have shallow breathing?

A
  • their liver is so big and takes up some of the room of the diaphragm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

3 parts of sternum

A
  • manubrium
  • body
  • xiphoid process
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

types of ribs

A
  • true ribs (1-7): articulate w/ sternum via costal cartilage
  • false ribs (8-10): articulate via costal arches
  • floating ribs (11-12): not connected to sternum at all, slope downward
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

typical vs atypical ribs

A
  • typical (3-9): ribs that have same components - head, neck, tubercle, body
  • atypical (all others): ribs that have unique structures
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

what important things does the sternal angle indicate?

A
  • RATPLANT (T4/T5)
  • Rib (2nd)
  • Arch of aorta
  • Tracheal bifurcation
  • Pulmonary trunk
  • Left recurrent laryngeal nerve + Ligamentum arteriosum
  • Azygos vein drains to SVC
  • Nerves - cardiac plexus
  • Thoracic Duct
  • (transthoracic plane - division of superior/inferior mediastinum)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

what happens re: CPR with kids vs adults?

A
  • kids have a very flexible thoracic cage whereas adults have brittle costal cartilage
  • therefore in kids = risk of compression of heart etc whereas adults = lungs @ risk of puncture
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

2 thoracic apertures

A
  • superior = connection to upper limb, head and neck
  • inferior = abdominal cavity + pelvis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

which structures travel through the superior aperture?

A
  • oesophagus
  • trachea
  • great vessels and nerves of head/neck and upper limbs
  • apex of lungs
48
Q

boundaries of the superior aperture

A
  • posterior, middle and anterior scalenes (connect neck to thoracic cage) - accessory muscles of breathing
  • suprapleural membranes
49
Q

boundaries of the inferior aperture

A
  • diaphragm
50
Q

3 spaces inside the thoracic cavity

A
  • pericardial cavity
  • pleural cavity
  • mediastinum
51
Q

how do thoracic spaces relate to central venous line placement?

A
  • X-ray needed before insertion to ensure you don’t hit brachial plexus or artery
52
Q

how do thoracic spaces relate to a liver exam?

A
  • use R costal margin
  • ask Pt to take deep breath
  • if more of the liver is palpable then normal > hepatomegaly
53
Q

describe the dome shape of the diaphragm

A
  • anteriorly and R, it is superior
  • posteriorly and L, it is inferior
54
Q

what are the 3 apertures in the bottom of the diaphragm and what structures pass through them?

A
  • T8 (caval hiatus): inferior vena cava and R phrenic n.
  • T10 (oesophageal hiatus): oesophagus and vagus n.
  • T12 (aortic hiatus): aorta and thoracic duct
  • I ate 10 Eggs At 12pm
55
Q

which muscles help w/ breathing in the various dimensions?

A
  • vertical: diaphragm
  • AP/transverse: intercostals
56
Q

describe inspiration

A
  • air sucked into lungs
  • increased volume = decreased thoracic pressure
  • diaphragm contracts and moves downwards = increased abdominal pressure
  • intercostals contract to move ribs up and out
57
Q

functions of intercostal muscles

A
  • fix the ribs
  • maintain or increase tone of intercostal space
  • resist pressure changes
  • assist w/ respiration by elevating ribs
58
Q

external intercostals:
- location
- fibre orientation
- when are they replaced by a membrane?
- when are they most active

A
  • more lateral
  • fibres run along inferoanteriorly (‘hands in pockets’)
  • replaced anteriorly by external intercostal membrane, approximately @ midclavicular line
  • most active during forced inspiration - elevate ribs
59
Q

internal intercostals:
- location
- fibre orientation
- when are they replaced by a membrane?
- when are they most active

A
  • more medial (deep to externals)
  • fibres run inferoposteriorly (‘hands on chest’)
  • replaced posteriorly by internal intercostal membrane, approximately @ midscapular line
  • most active during forced expiration - depress ribs
60
Q

innermost intercostals

A
  • deep to internal intercostals
  • deep to intercostal neurovascular bundle
  • similar fibre orientation to internal intercostals (hands on heart)
61
Q

subcostal muscles

A
  • form bridges across the INTERNAL SURFACES from one rib to 2-3 ribs below
  • (whereas intercostals only bridge two adjacent ribs)
62
Q

transverse thoracic muscles
- location
- function

A
  • attach internal surfaces of costal cartilages 2-6 to POSTERIOR sternum
  • accessory muscles to respiration when bent over
  • aid in proprioception
63
Q

what is the lung hilum?

A
  • where the bronchi attach to the lungs
64
Q

what is the pleura?

A
  • simple epithelial layer (mesothelium - comes from mesoderm)
  • double layered sac (technically one layer that doubles on itself)
  • the pleural cavity (between the layers) contains fluid to decrease friction during breathing
65
Q

why is the pleural cavity called a potential space?

A
  • as lungs continue to grow, pleural cavity gets smaller and there is basically no space
  • if lung collapses or there is a haemothorax or pneumothorax, this space can get bigger
  • can use X-ray to guide thoracentesis
66
Q

pulmonary ligament

A
  • connects visceral and parietal pleura
67
Q

what is a point of reflection

A
  • when visceral pleura turns into parietal (b/c it wraps around itself)
68
Q

describe the difference between the serous membrane surrounding the heart vs lungs

A
  • heart has visceral, parietal and then fibrous pericardium (superficial to parietal)
  • lungs only have visceral and parietal
69
Q

layers of tissue in the thorax or abdomen

A
  • 1) skin
  • 2) superficial and deep fascia
  • 3) muscles
  • 4) endothoracic fascia or extraperitoneal connective tissue
  • 5) parietal pleura or peritoneum
  • 6) visceral pleura or peritoneum
70
Q

intercostal neurovascular bundles

A
  • run within subcostal groove (between internal and innermost intercostals)
  • from superior to inferior: vein, artery, nerve
  • vein is most protected due to rib, nerve is least protected
  • posterior intercostal vessels arise from thoracic aorta
  • anterior intercostal vessels arise from internal thoracic artery or musculophrenic artery
71
Q

which vessels supply the intercostal spaces?

A
  • 1-6: branches of internal thoracic artery
  • 7-9: musculophrenic artery
72
Q

when would anterior and posterior intercostal arteries anastomose?

A
  • increase in demand for blood
  • blockage or narrowing of arteries
73
Q

how to know whether layers of back muscles originated at the front or back of the embryo?

A
  • ‘true’ back muscles are innervated by dorsal rami of mixed spinal nerves, usually deeper
  • superficial back muscles are innervated by branches of brachial plexus > started anteriorly
74
Q

what structures do the intercostal nerves innervate in order?

A
  • muscle, then skin, then pleura
75
Q

describe the course of intercostal nerves 7-11

A
  • continue across subcostal margin to supply anterolateral abdominal wall
  • considered thoracoabdominal nerves
  • only area where the cutaneous innervation matches w/ dermatomes
76
Q

what is the cardiophrenic angle?

A
  • the angle formed b/n the diaphragm and the right atrium of the heart on an X-ray
77
Q

what is the costophrenic angle?

A
  • the angle formed b/n the diaphragm and the ribs on an X-ray
78
Q

why does the heart have a fibrous pericardium (extra parietal layer?)

A
  • lungs expand and push their parietal pleura into the heart > 3rd layer
  • (the 1st and 2nd layers are formed when the heart migrates into the thorax)
79
Q

which layer of the pericardium is more sensitive to pain?

A
  • parietal (serous and fibrous) b/c comes into contact w/ somatic nerve
80
Q

innervation of pericardium

A
  • sensory: phrenic n.
  • vagus nerve (unknown function)
  • sympathetic trunk = vasomotor
81
Q

branches of right coronary artery

A
  • gives off SA nodal a. (in 60% of cases)
  • then gives off right marginal a. (supplies R ventricle) and posterior interventricular/descending a. (supplies posterior and inferior walls of left ventricle)
  • posterior descending a. is only supplied by R coronary a. when heart is R dominant
82
Q

what parts of the heart does the RCA supply?

A
  • R atrium
  • most of R ventricle
  • diaphragmatic surface of L ventricle - posterior 1/3 of interventricular septum
83
Q

branches of left coronary artery

A
  • gives off circumflex artery which then gives off left marginal a. and SA nodal a. (in 40% of cases)
  • also gives off LAD (supplies anterior 2/3 of septum and ventricles)
84
Q

what happens re: vasculature in a LEFT dominant heart?

A
  • since the posterior descending a. is supplied by the L coronary a., the entire L ventricle and septum will be perfused by the LCA
  • therefore the RCA only supplies the R ventricle
  • if there’s blockage to the left side we completely lose blood supply to everything except the R ventricle
  • called a widowmaker’s MI because youre fucked lol
85
Q

key venous drainage of the heart

A
  • coronary veins (great, middle and small cardiac veins) drain into coronary sinus > drains into R atrium
86
Q

coronary artery and vein pairings

A
  • LAD with greater cardiac vein
  • PDA with middle cardiac vein
  • R marginal branch (RCA) with small cardiac vein
87
Q

where do the coronary arteries originate

A
  • from the root of the aorta, just superior to the aortic valve leaflets
88
Q

which parts of the cardiac conduction system does the RCA supply?

A
  • SA node + AV node
89
Q

how do the coronary arteries fill up?

A
  • blood collects in the concave leaflets of the aortic and pulmonary valves
  • coronary vessels fill during diastole (rest)
90
Q

what are A, B, C

A
  • A = LCA
  • B = LAD
  • C = RCA
91
Q

what are D, E, F

A
  • D = LCx
  • E = 1st marginal artery
  • F = 2nd marginal artery
92
Q

what are G, H?

A
  • G = acute marginal artery
  • H = PDA
93
Q

clinical relevance of filling of coronary arteries via cusps of valves

A
  • if valves don’t work then arteries won’t fill up > poorer perfusion of heart even tho arteries themselves may be working fine
94
Q

impact of heart hypertrophy

A
  • hypertrophy can be caused by blockage > blood pools > heart pumps stronger to try and get it out > muscle cells hypertrophy
  • leads to decreased space for blood which further perpetuates the cycle
95
Q

cardiac conduction system

A
  • SA node: primary pacemaker, triggers atrial contraction
  • AV node: secondary pacemaker
  • bundle of His > divides into R and L branches
  • R branch runs along the moderator band, ending @ anterior papillary muscle
  • L branch divides into 3 branches
  • Purkinje fibres in papillary muscle of ventricles
96
Q

sensory innervation of the heart

A
  • sensory fibres enter spinal cord @ T1-T5 > referred pain in chest, shoulder and upper limb
97
Q

sympathetic innervation of the heart

A
  • SHORT presynaptic nerve: T1-T5 roots
  • synapse in cervical ganglia
  • LONG postsynaptic nerves go to bifurcation of trachea, over aortic arch and PT, then go to innervate the heart
98
Q

what are the 3 cervical ganglia?

A
  • contribute to postsynaptic sympathetic imput of the heart
  • superior, middle and inferior (stellate) ganglia
  • lead to superior, middle and inferior cardiac nerves
99
Q

parasympathetic innervation of the heart

A
  • LONG presynaptic: vagus nerve starts @ brain stem
  • synapse on cardiac ganglia
  • post synaptic fibres go and perform function
100
Q

what is the cardiac plexus made of?

A
  • postsynaptic sympathetic
  • presynaptic parasympathetic
101
Q

3 layers of the heart

A
  • endocardium: tunica intima - endothelium
  • myocardium
  • epicardium (visceral pericardium)
102
Q

describe the myocardium

A
  • tunica media - thickest layer, cardiac muscle
  • cardiac muscle cells are branched, have a cytoplasm packed with myofibrils, large central nuclei
  • high density of capillaries to provide O2 for contractions
  • purkinje fibres
103
Q

describe the epicardium

A
  • visceral pericardium
  • tunica adventitia - thick layer of loose connective tissue w/ adipose tissue
  • squamous mesothelium and basal lamina cover the external surface
  • contains coronary arteries and nerves supplying the heart which branch into the myocardium
104
Q

why do Purkinje fibres stain lighter?

A
  • due to presence of glycogen
105
Q

structure of cardiac muscle cells

A
  • branched cells w/ one nucleus (sometimes two)
  • striated (involuntary)
  • has sarcomeres between Z lines with A (dark) and I (light) bands
  • T tubules and only one associated piece of sarcoplasmic reticulum form dyads (not triads) @ Z lines
  • cardial muscle cells joined end-to-end via intercalated discs (gap junctions, fascia (zonula) adherens + desmosomes) - physical and electrical connection for contraction
  • many mitochondria
106
Q

what is cardiac tamponade?

A
  • when excess fluid puts pressure on ventricles > reduced heart function
107
Q

2 pericardial sinuses

A
  • transverse: separates aorta and pulmonary trunk from superior vena cava
  • oblique: behind left atrium , between R and L pulmonary veins
108
Q

tetraology of fallot

A
  • pulmonary stenosis
  • right ventricular hypertrophy
  • ventricular septal defect
  • overriding aorta
109
Q

where in the heart do the pulmonary veins enter?

A

left atrium

110
Q

where are the papillary muscles and chordae tendineae?

A
  • L and R ventricles
111
Q

where is the Triangle of Koch?

A
  • R atrium
  • indicates location of AV node
  • borders: IVC, coronary sinus and tricuspid valve
112
Q

what is the most common congenital malformation of the great vessels?

A
  • coarctation (narrowing) of the aorta
  • reduced blood flow to lower body and high pressure in upper body
113
Q

left vs right heart failure

A
  • LHF: L ventricle can’t pump effectively = pressure accumulates in pulmonary system = pulmonary oedema + SOB
  • RHF = R ventricle can’t pump properly = pressure accumulates in systemic system = peripheral, pitting oedema and jugular vein distention
114
Q

structural differences b/n purkinje fibres and cardiomyocytes

A
  • cardiomyocytes are:
  • larger
  • lighter stained due to high glycogen content
  • 2 nuclei w/ white ring around them
  • no intercalated discs
  • more mitochondria
115
Q

describe the structure of the aortic arch

A
  • 3 branches
  • R branch is called brachiocephalic trunk. bifurcates into subclavian artery (lateral) and R common carotid (medial)
  • middle branch is L common carotid
  • L branch is L subclavian artery
116
Q

structural differences b/n atrial and ventricles

A
  • atria have crista terminalis and pectinate muscles (irregular ridges/muscles)
  • ventricles have papillary muscle, chordae tendineae and septomarginal trabecula (moderator band)
117
Q

causes for systolic vs diastolic murmur

A
  • systolic: aortic stenosis, mitral regurgitation (due to chordinae tendineae rupture)
  • diastolic: mitral stenosis, aortic regurgitation