Exam 1 Flashcards
Scapular line
Passes through inferior angle of scapula
Thoracic vertebrae with only one costal facet
TV1, 10, 11, 12
Type of attachment between 1st rib and sternum
Synchondrosis
True ribs
Attach directly to sternum
Ribs 1-7
False ribs
Attach to sternum via costal margin
Ribs 8-10
Floating ribs
Don’t attach to sternum
Ribs 11 and 12
Atypical ribs
Have the number 1 or 2 in them
Ribs 1, 2, 10, 11, 12
Attachment of anterior scalene m
Attaches to superior surface of 1st rib.
Subclavian v passes anterior to m, subclavian a passes posterior to m
Which rib attaches at sternal angle?
2nd rib
Which rib attaches at xyphi-sternal joint?
7th rib
Transverse thoracic plane
Line from sternal angle to disc between TV4 and 5
Most common site of rib fx
Angle of rib
Most common site of rib separation
Costochondral joint
What type of joints are sternocostal joints?
Synovial joints
Course of intercostal V/A/N
Between internal and innermost intercostal mm, on inferor aspect of rib through costal groove.
Superior to inferior: V→A→N
Endothoracic fascia
Lines inside of chest cavity
T4 dermatome
Found around the level of where the nipples should be
T10 dermatome
Found around the umbilicus region
Intercostobrachial n
Comes from T2
Internal thoracic a branches
Bifurcates at about the level of 6th rib
Forms superior epigastric a and musculophrenic a
Superior epigastric a
Supplies mm of rectus abdominis
Musculophrenic a
Supplies anterior intercostal aa to lower intercostal spaces
What forms intercostal nn?
Ventral rami of spinal nn
Structures found at the transverse thoracic plane
Ligamentum arteriosum
Concavity of aortic arch
Bifurcation of pulmonary trunk
Vagus n becomes plexiform
Bifurcation of trachea at carina
What vessels join behind the 1st rib?
R and L brachiocephalic vv
Length of superior vena cava
Extends from level of 1st rib to 3rd rib
Cord levels of phrenic n
Arises from C3, 4, 5
Anterior mediastinum contents
Fat, lymph nodes, connective tissue, thymus remnants
What plane does the esophagus begin at?
C6
Course of the esophagus
Begins off to the left, then curves to the right in middle thorax because of the aorta, then back to the left to pierce the diaphragm and join the stomach.
Level of pharyngoesophageal constriction
C6
Level of thoracic constriction of esophagus
T4/5
Level of diaphragmatic constriction of esophagus
T10
Formation of azygous v
R ascending lumbar vein joins R subcostal v to form azygous v on R side of body
Formation of hemiazygous v
L ascending lumbar v joins L subcostal v to form hemiazygous v on L side of body. Drains 9th-11th intercostal vv and subcostal v on L side. Will cross midline to drain into azygous v.
Formation of accessory hemiazygous v
5th-8th intercostal vv on L side of body join to form accessory hemiazygous v. Will cross midline to drain into azygous v
Cisterna chyle
Origin of thoracic duct at LV2. Collects lymph from R and L lower extremities, pelvis, and abdomen
What does the thoracic duct drain?
Both lower extremities, pelvis, abdomen, L upper extremity, L half of thorax, L half of head and neck
Contents of greater splanchnic n
Preganglionic sympathetic nn fibers from T5-9
Contents of lesser splanchnic n
Preganglionic sympathetic nn fibers from T10 and 11
Contents of least splanchnic n
Preganglionic sympathetic nn fibers from T12
Where do greater/lesser/least splanchnic nn synapse
In pre-aortic ganglia in abdomen
R main bronchus vs L main bronchus
R main bronchus is shorter, wider, and directed more straight downward than L main bronchus
Costomediastinal recess
Medial edge of parietal pleura
Costodiaphragmatic recess
Space at base of lungs
Pulmonary ligament
Point at which visceral pleura reflects to become parietal pleura; serves to anchor lung
Innervation of pleura
Phrenic n
Pleurisy
Inflammation of pleural lining
Orientation of A/V/ Bronchi in L lung
A will be superior, V will be anterior and inferior, bronchi will be more posterior
Orientation of A/V/Bronchi in R lung
A is most anterior, V is in middle, bronchus is posterior
Pulmonary lymph nodes
Found within lung tissue
Bronchopulmonary lymph nodes
Found at hilum (junction of bronchus and lung tissue)
Trachiobronchial lymph nodes
2 sets: superior and inferior.
Inferior sit below carina, also called carinal lymph nodes
Paratracheal lymph nodes
Sit beside trachea
Pancoast tumor
Found in superior lobe of lung. Can affect brachial plexus and cervical sympathetic ganglia
Sx of Pancoast Syndrome
Pain in shoulder radiating towards axilla and scapula, pain along ulnar aspect of hand, atrophy of hand and arm mm, Horner’s Syndrome (ptosis, miosis, anhydrosis)
Virchow’s node
Abnormally enlarged L supraclavicular lymph node. Sometimes called “seat of the devil”
Components of pericardium
Fibrous component and serous component
Sulcus terminalis
Sulcus between superior/inferior vena cava and R atrium
Function of the fibrous skeleton of heart
- Keeps the 4 valve orifices patent
- Site of valve attachment/anchoring
- Site of muscle attachment
- Electrically insulates atria from ventricles
- Provides a tunnel for the AV bundle
Ratio of thickness of atrial wall : R ventricular wall : L ventricular wall
1:3:9
Where do you find preganglionic sympathetic nerve cell bodies?
Intermediolateral cell column of grey from T1-L2
Sympathetic innervation of heart
7 pairs of cardiopulmonary splanchnic nn, carrying postganglionic sympathetic fibers
Parasympathetic innervation of heart
6 pairs of vagal cardiopulmonary nn carrying preganglionic parasympathetic fibers
Average diameter of RBC
~7µm
Blood capillaries vs lymphatics
Blood capillaries tend to have uniform diameter
Lymphatic capillaries have variable diameters and incomplete basement membranes
Pericyte
Accessory cells that sit on top of blood vessels. Seem to be a precursor cell of sorts; often differentiate into smooth muscle cells
3 types of capillaries
Continuous capillaries
Fenestrated capillaries
Discontinuous capillaries
Discontinuous capillaries
Much larger than other types of capillaries. Found in locations where large amounts of exchange of materials is needed, i.e. liver, spleen, pancreas.
Inner elastic lamina
Deepest portion of tunica intima. Not visible in smaller arteries, but in larger ones it can be seen. Composed of mostly elastic fibers.
Number of layers of smooth muscle in an arteriole
No more than ~5 layers of smooth muscle
Subendocardial connective tissue
Found within the endocardium. Purkinje fibers found here.
Mesothelium
part of the visceral covering of the heart
Lacteal
Lymph collecting channel found in periphery, immediately juxtaposed with capillary beds.
What part of the embryo gives rise to the heart?
The mesoderm of the early cardiogenic field
Sinus venosus
Initially receives common cardinal v, umbilical v, and vitelline v. Will eventually become sinus venarium of R atrium.
Primitive atrium
Forms the portion of atria that contains pectinate mm, called auricles
Primitive ventricle
Develop trabeculae carnae of the L ventricle
Bulbus cordis
Consists of three parts.
First part will form trabeculated portion of R ventricle
Second part will form outflow tracts of both ventricles: aortic vestibule of L ventricle and conus arteriosus of R ventricle
Third part, the truncus arteriosus, will form the ascending aorta and pulmonary trunk
Partitioning of atria
Step 1: Septum primum forms
Step 2: Osteum primum forms, is the initial blood shunt from R to L. Very short lived.
Step 3: Osteum primum closes
Step 4: As osteum primum closes, osteum secundum forms from region of apoptosis in septum primum
Step 5: Septum secundum forms in R atrium
Step 6: septum primum is incomplete; contains opening called foramen ovale
Septum primum now called valve of foramen ovale
Partitioning of atrioventricular canals
Bulboventricular flange regresses and atrioventricular canal opens. Neural crest cells migrate in and form endocardial cushion around AV canal. Superior and inferior endocardial cushions grow towards each other and fuse.
What are heart valves derived from?
Neural crest cells
Intraventricular septum parts
2 parts: muscular and membranous.
Muscular part derived from muscle of ventricle wall
Membranous portion derived from endocardial cushions
Conotruncal ridges
Derived from neural crest cells. Will divide the conus cordis and truncus arteriosus. Also called aorticopulmonary septum and spiral septum.
Ventricular septal defects
Most common congenital anomaly
Endocardial cushion defects
Neural crest in origin.
Tetralogy of Fallot
Caused by unequal division of truncus arteriosus by conotruncal ridges. Has four components:
Pulmonary stenosis
Overriding aorta
Interventricular septal defect
R ventricular hypertrophy
Transposition of great vessels
Caused by failure of conotruncal ridges to spiral.
Blood from R heart goes into aorta, blood from L heart goes into pulmonary circuit. Mixing occurs via patent ductus arteriosus
Persistent truncus arteriosus
Caused by failure of conotruncal ridges to form
DiGeorge Syndrome
CATCH-22
Deletion on chromosome 22 causes neural crest disorder
Cardiac defects (endocardial cushions and conotruncal ridges)
Abnormal facial development
Thymic aplasia
Cleft palate
Hypocalcemia (parathyroid deficiency)
Vasculogenesis
de novo synthesis of new vessels. Mostly a prenatal process.
Angiogenesis
Sprouting of vessels from existing vessels. Occurs postnatally.
Development of arterial system from aortic arches
1st and 2nd aortic arches regress
Dorsal aorta that connected 3rd and 4th arches regresses BIL
Connection at bottom also regresses
5th aortc arch regresses
What embryonic artery does the common carotid artery arise from?
3rd aortic arch artery
What embryonic artery does the arch of the aorta form from?
L 4th aortic arch artery
What embryonic artery does the right subclavian artery arise from?
R 4th aortic arch artery
What embryonic artery forms the ductus arteriosus?
L 6th aortic arch artery
Coarctation of the aorta
Results from a constriction of part of the aorta. 2 types: preductal and postductal.
Cardiac rate and rhythm are reproducible due to what?
Automaticity (no neural input required)
Conduction system
Functional syncytium
How is Ca++ removed from cardiomyocytes?
3Na+/1Ca++ antiporter on sarcolemma
Ca++ pump on sarcolemma
Smooth Endoplasmic Reticulum Calcium ATPase (SERCA)
Early afterdepolarization
Occurs in late phase 2 or early phase 3 of cardiac cycle. More likely when AP duration is prolonged. Reentry is more likely to occur than with delayed afterdepolarizations
Long QT Syndrome
Mutation in channels that results in prolonged AP in cardiac tissue. Associated with development of Torsades de Pointes
Delayed afterdepolarizations
AP generated during phase 4 of cycle, but before a normal AP would occur. Associated with increased [Ca++]i
Factors promoting reentry
- Lengthened conduction pathway
- Decreased conduction velocity
- Reduced refractory period
EKG indication of RVH
Tall R wave in V1 followed by decreasing amplitude through precordial leads
EKG indication of LVH
S in V1 + R in V5 is more than 35mm
Which circulatory segment does the greatest pressure drop occur across?
Arterioles
What is the driving force for blood flow?
Mean arterial pressure
Mean arterial pressure equation
At rest: MAP = DBP + 1/3(SBP - DBP)
During exercise: MAP = DBP + 1/2(SBP - DBP)
Fick Principle
Cardiac output = oxygen consumption / arterial - venous O2difference
Q = VO2 / (A-V) O2 Difference
Causes of increased turbulent flow
Increase in velocity
Increase in diameter
Decrease in viscosity
What is compliance?
Measure of vessel distensibility.
Compliance = change in vol / change in pressure
Ohm’s Law applied to blood flow
Flow = change in pressure / vessel resistance
Relationship between CO, MAP, and TPR
CO = MAP / TPR
Extrinsic control of vascular resistance
Neural (mediated by sympathetic nervous system and alpha1 receptors)
Endocrine
Intrinsic control of vascular resistance
Autoregulated: flow is independent of blood pressure, proportional to tissue metabolism
Examples: cerebral circ, coronary circ, skeletal musc. during exercise, renal circ
Starling Forces
Pc: Capillary hydrostatic pressure
Pi: Interstitial fluid hydrostatic pressure
πc: Capillary colloid osmotic pressure
πi: Interstitial colloid osmotic pressure
What are the most important factors influencing filtration/reabsorption?
Capillary hydrostatic pressure
Plasma colloid osmotic pressure
Factors that promote edema
Increased capillary pressure
Increased capillary permeability
Decreased plasma oncotic pressure
Lymphatic blockage
During contraction, on which part of the heart are coronary vessels more likely to be compressed? Least likely?
Most likely: Left ventricle
Least likely: Right ventricle
Coronary Steal
If a vessel is stenosed, tissue downstream has decreased flow. If vasodilators are given, because the stenosed vessel is maximally dilated, dilation of other vessels will decrease flow to the stenosed vessel. This will decrease available supply to the area downstream of the stenosis.
Contents of esophageal plexus
Postganglionic sympathetic fibers and preganglionic parasympathetic fibers
Which embryonic vessel forms the superior vena cava?
R common cardinal v
Which embryonic vessel forms the inferior vena cava?
R subcardinal v
What is the mechanism of absent inferior vena cava?
R subcardinal v fails to make a connection with the hepatic part of inferior vena cava. Results in the caudal portion of the body being drained by the azygous venous system.
What is the mechanism of a left superior vena cava?
L common cardinal v persists, forming a L superior vena cava. This causes R common cardinal v to regress. L superior vena cava drains to R atrium via coronary sinus.
What is the mechanism of double superior vena cava?
R and L common cardinal vv persist, forming R and L superior venae cava. R superior vena cava drains into R atrium as per normal. L superior vena cava drains into R atrium via coronary sinus.
What becomes of the umbilical v postnatally?
Forms ligamentum teres hepatis
