Cardiopulmonary 1 - Midterm; Anatomy & Embryology Flashcards
What embryonic tissue is the respiratory system derived from?
Endoderm (specifically - fore gut endoderm)
During which week of development does the tracheoesophageal folds fuse?
Week 5
The fusing of the tracheoesophageal folds during week 5 of development forms what structure?
Tracheoesophageal Septum
In the trachea, what embryologic tissue forms the epithelium, glands, and pulmonary epithelium?
Endoderm (specifically - fore gut endoderm)
What embryologic tissue gives rise to cartilage, connective tissue, and smooth muscle of the trachea?
Splanchnic Mesenchyme
Specifically - Splanchnic Layer of Lateral Plate Mesoderm
What defect causes abnormal passage between trachea and esophagus?
Tracheoesophageal Fistula
Which occurs in combination with Esophageal Atresia in 85% of cases
What is a “blind end esophagus” called?
Esophageal Atresia
During which week of development does the lung bud form?
Forms from endoderm during week 4.
During which week of development are primary bronchial buds formed?
Week 5
During which week of development are secondary bronchi formed?
Week 6
During which week of development are tertiary bronchi formed?
Week 7
During week 6 of development, how many secondary bronchi are formed on the right side?
3 (superior, middle, inferior)
During week 6 of development, how many secondary bronchi are formed on the left side?
2 (superior, inferior)
During week 7 of development, how many tertiary bronchi are formed on the right side?
10
During week 7 of development, how many tertiary bronchi are formed on the left side?
9
At completion of Bronchopulmonary segment branching at 24 weeks, how many orders of branching are there?
17 orders of branches, terminal bronchioles
At what week of development do the bronchopulmonary segments complete branching, thus completing formation of the conducting system of the lungs?
week 24
17 orders of branches, terminal bronchioles
What are the weeks of Pseudoglandular Stage of Lung Development?
5-17 weeks
What is formed during the Pseudoglandular Stage of Lung Development?
- terminal bronchioles formed - connective tissue - CANNOT survive if born - NO gas exchange possible
What weeks during lung development compose the Canalicular Stage?
16-25 weeks
What events occur during the Canalicular Stage of Lung Development?
- Vascularization
- Respiratory Bronchiole
formation
> formation of primordial
alveolar ducts - Terminal sacs formed
(primitive alveoli) - +/- survival of fetus if born
Which bronchioles does the terminal bronchioles develop into?
Respiratory Bronchioles (primordial alveolar ducts), which happens during the Canalicular Stage (16-25 weeks) of Lung Development.
What stage of lung development occurs from roughly 24 weeks until birth?
Terminal Sac Stage (or Saccular Stage)
What events take place during the terminal sac (saccular) stage of lung development?
- Gas Exchange
- Squamous Epithelium = Type I Pneumocytes
- Type II Pneumocytes (produce surfactant)
- infant will survive if born
What do terminal sacs from the terminal sac (saccular) stage of lung development give rise to?
Become Mature Aleoli
What pulmonary cell type is responsible for gas exchange?
type I pneumocytes
What type of epithelium are type I pneumocytes?
squamous epithelium
What type of epithelium are type II pneumocytes?
secretory epithelium
Which pulmonary cell type produces surfactant?
type II pneumocytes (secretory epithelium)
During what stage of lung development does surfactant production begin?
Terminal Sac (Saccular) Stage [24 weeks - birth]
What stage of lung development occurs from roughly 32 weeks - 8 years of age?
Alveolar Stage
What events occur during the Alveolar Stage of Lung Development?
- Alveolocapillary membrane formation
- Primitive Alveoli formation (which then form more primitive alveoli)
- Mature Alveoli formation
At what age does maturation of most alveoli occur?
3 years of age
What percentage of alveoli are mature at normal gestational birth?
5%
What clinical condition can be caused by too much surfactant in one area?
Tension Pneumothorax
What events are required for normal lung development?
1) fetal breathing movements (FMBs)
2) adequate thoracic space for growth
3) adequate amniotic fluid volume
Where and why does fetal breathing movements (FBMs) occur?
Occur in-utero with sufficient force to cause aspiration of amniotic fluid.
By way of which 3 mechanisms are intra-alveolar fluid cleared at birth of fetus?
1) through mouth & nose by pressure on fetal thorax during vaginal delivery
2) into pulmonary capillaries, arteries, and veins
3) into lymphatics
** steps 2 & 3 critical in C-section deliveries **
What does severe and chronic oligohydramnios cause?
- Retards lung development and may result in PULMONARY HYPOPLASIA.
Pulmonary Hypoplasia –> is at greater risk if oligohydramnios occurs prior to 26 weeks of gestation.
During which portion of lung development is risk of pulmonary hypoplasia significantly increased?
Oligohydramnios occurring prior to 26 weeks of gestation.
What is formed by the fusion of the 2 endocardial primordia?
Endocardium
What membrane separates the pericardial cavity from the pleural canals?
Pleuropericardial Folds (membrane)
Between which 2 membranes does the lungs develop?
Between Pleuropericardial Membrane and the Pleuroperitoneal Membrane.
From what embryonic tissue are the pleuropericardial folds derived?
Somatic Layer of Lateral Plate Mesoderm
From what embryonic tissue is the visceral pericardium derived?
Splanchnic Layer of Lateral Plate Mesoderm
From what embryonic tissue is the serous and fibrous pericardium derived from?
Somatic Layer of Lateral Plate Mesoderm
The Phrenic N. runs in what fold?
The Pleuropericardial Folds.
The pleuroperitoneal membranes migrate anteriorly to fuse with what?
Septum Transversum
What cavity is located inferior to the septum transversum and pleuroperitoneal membrane?
peritoneal cavity
What does the septum transversum become?
central tendon of the diaphragm
What gives rise to crura?
Dorsal Mesentery of Esophagus
List 5 signs/symptoms of respiratory distress syndrome?
- Tachypnea
- Nasal flaring
- Suprasternal, Interconstal, or Subcostal Retractions
- Grunting
- Cyanosis
What are 2 key finds on a chest X-ray in RDS patients?
- low lung volumes
- diffuse reticulogranular ground glass glass appearance
What causes RDS?
pt lacks sufficient surfactant production
** surfactant production occurs at 24 weeks during the saccular stage of lung development
List findings during physical examination of an infant with a congential diaphragmatic hernia.
- barrel-shaped chest
- scaphoid appearing abdomen
- absence of breath sounds on ipsilateral side
- if hernication on left side, heart beat is displaced to right due to mediastinal shift
What is the embryological cause of a congential diaphragmatic hernia?
Pleuralperitoneal folds (membrane) did not migrate & fuse with septum transversum correctly.
(**typically occurs on the left side)
What is the embryological cause of esophageal atresia and/or tracheoesophageal fistula?
Esophageal folds did not come together & fuse correctly to form the tracheoesophageal septum during week 5 of development.
During what week of development does the esophageal folds migrate and fuse to form the tracheoesophageal septum?
week 5
List a prenatal sign sign in 2/3 of tracheoesophageal fistula patients?
mother has polyhydramnios
List signs/symptoms seen in infant @ birth with tracheoesophageal fistula.
- coughing
- gagging
- cyanosis
- vomiting
- voluminous oral secretions
- possible respiratory distress
What is the cause of congenital lung cysts?
Though to result from disturbance in bronchial development during late fetal life.
What are the 2 terminal branches of the Internal Thoracic A.?
- Musculophrenic A. (lateral)
- Superior Epigastric A. (medial)
[continues inferiorly, deep to rectus abdominous m.]
What Artery gives off Anterior Intercostal As.?
Internal Thoracic A.
What artery arises from the Internal Thoracic A. around the 2nd rib?
Pericardiacophrenic A.
What artery does the Internal Thoracic A. arise from?
Subclavian A.
Does the Internal Thoracic A. course superficial or deep to the Transverse Thoracic Ms.?
Superficial
meaning, you would hit the internal thoracic a. and then the transverse thoracic ms.
From which artery does Medial Mammary A. arise?
Internal Thoracic A.
What are the 4 arterial branches coming off of the descending thoracic aorta?
- Unpaired Visceral Branches
(visceral - go to viscera)
> mediastinal A.
> esophageal A.
> pericardial A.
- Paired Lateral Visceral Branches
(visceral - go to viscera)
> bronchial A. - Paired Segmental Parietal Branches
(parietal - follow body wall)
> posterior intercostal a. - Superior Phrenic A.
What are the branches that arise from the posterior intercostal arteries?
- dorsal branch a.
- collateral branch a. (travel down & run along superior border of rib below)
- lateral cutaneous a. (travel through intercostal ms. and go to supply skin)
[**lateral cutaneous a. gives rise to Lateral Mammary Branch]
What are the 2 arterial sources that can give rise to a Lateral Mammary Branch?
- Lateral Mammary Branch (from Lateral Thoracic A.)
[**recall: lateral thoracic a. supplies the serratus anterior muscle] - Lateral Mammary Branch (from Lateral Cutaneous Branch of Posterior Intercostal A.)
What artery arises from the descending thoracic aorta just prior to passing through the aortic hiatus?
Superior Phrenic A.
List the 3 arteries that supply the superior portion of the diaphragm and the arteries that they arise from.
- Musculophrenic A. (from Internal Thoracic A.)
- Pericardiacophrenic A. (from Internal Thoracic A.)
- Superior Phrenic A. (from Descending Thoracic Aorta)
List the right arteries in order starting at the pulmonary trunk.
Pulmonary Trunk –> R. Pulmonary A. –> R. Superior Lobar A. (apical segment, posterior segment, anterior segment) –> R. Middle Lobar A. (lateral segment, medial segment) –> R. Inferior Lobar A. (superior segment, posterior basal segment, medial basal segment, anterior basal segment, lateral basal segment)
What vein runs with the posterior interventricular artery in the posterior interventricular groove?
Middle Cardiac V.
What vein runs with the anterior interventricular artery in the anterior interventricular groove?
Great Cardiac V.
What vein runs in the horizontal plane and passes just superficial to the right coronary artery?
Anterior Cardiac Vs.
What vein runs around the right side of the heart and empties into the coronary sinus along with the great cardiac and middle cardiac veins?
Small Cardiac V.
Which 2 arteries arise from the ascending aorta?
- Left Coronary A.
- Right Coronary A.
What are the branches off of the Right Coronary A.?
- Sinuatrial Nodal A.
- Conus Branch of Right Coronary A.
- Atrial Branch of Right Coronary A.
- Right Marginal A.
- Atrioventricular Nodal A.
What are the 2 terminal branches of the Right Coronary Artery?
- Right Posterolateral A.
- Posterior Interventricular A.
What are the branches of the Left Coronary A.?
- Circumflex Branch of the Left Coronary A. (or Circumflex A.)
- Anterior Interventricular Branch of the Left Coronary A. (or Anterior Interventricular A.)
- Left Marginal A. (arising from circumflex a.)
- Posterior Left Ventricular A. (arising from circumflex a.)
What arteries arise from the aortic arch?
- brachiocephalic trunk
- left common carotid a.
- subclavian a.
What vein runs with the right marginal a.?
Small Cardiac V.
Compare and contrast where the small cardiac v. and anterior cardiac v. empty?
- Small Cardiac V. –> coronary sinus
- Anterior Cardiac V. –> right atrium
In the course of the Great Cardiac V., what arteries does it run with depending on where it’s located?
- Great Cardiac V & Circumflex A.
- Great Cardiac V. & Anterior Interventricular A.
What artery runs in the right atrioventricular groove?
Right Coronary A.
Where does the azygous v. empty into?
Superior Vena Cava
What vein does the Right Posterior Intercostal Vs. always empty into?
Azygous V.
What veins do the Left Posterior Intercostal Vs. empty into?
- Hemiazygous V.
- Accessory Hemiazygous V.
** which come together and empty into the azygous v., and then into the superior vena cava **
What areas are lymphatics drained by the Thoracic Duct?
- lower extremities
- pelvis
- abdomen
- left half of thorax
- left upper extremity
- left side of head & neck superiorly
- subclavian lymphatic trunk & bronchomediastinal trunk in thorax
Where does the Thoracic Duct empty into?
Venous system near junction of Left Internal Jugular V. & Left Subclavian V.
List the 4 constriction points in which lodging typically occurs in the esophagus.
(listed superior to inferior)
1. Cricopharyngeus (muscle) Part of Inferior Pharyngeal Constrictor
- Arch of Aorta
- Left Main Bronchus
- Diaphragmatic Constriction (inferior esophageal “sphincter”)
True or False:
The Superior and Middle Cardiac Branches of the Vagus N. branch off once the Vagus N. is in the thorax.
False
Both branches arise from the Vagus N. in the neck.
True or False:
The Inferior Cardiac Branch of the Vagus N. branches off from from the Vagus N. in the neck.
False
Branches from Vagus N. when in the thorax.
Which Vagus N. (left or right) primarily contributes to the Anterior Vagal Trunk?
Left Vagus N.
Which Vagus N. (left or right) primarily contributes to the Posterior Vagal Trunk?
Right Vagus N.
What major artery does the Right Recurrent Laryngeal N. pass deep to on its way to innervate the larynx ?
Right Subclavian Artery
Which anterior rami fibers are carried by the Phrenic N.?
C3, C4, & C5
C3, 4, 5 keep the diaphragm alive
What muscle does the Phrenic N. course along on its way into the thorax?
Anterior Scalene M.
**recall: happening on both sides (bilateral)
Between what structures is the Phrenic N. sandwiched between as it courses through the thorax to the diaphragm?
> mediastinal parietal pleura
> fibrous pericardium
Which nerves is sandwiched between the mediastinal parietal pleura and fibrous pericardium in the thoracic cavity?
Phrenic N.
What 3 branches are given off of the Intercostal Ns.?
> collateral branch of intercostal N.
lateral cutaneous branch of intercostal N.
anterior cutaneous branch of intercostal N.
Which intercostal Ns. are the “Typical” Intercostal Nerves?
3-6 Intercostal Nerves
Which Intercostal Ns. are the “Atypical” Intercostal Nerves?
1-2 and 7-11 Intercostal Nerves
What do Intercostal Nerves 7-11 turn into on the anterior side of the body?
Thoracoabdominal Nerves
True or False:
All gland secretions are controlled by parasympathetic, except sweat glands.
TRUE
** very important to know!! **
What vertebral level does the inferior vena cava pass through the diaphragm?
T8
** is also the level of the ventricles of the heart **
At what vertebral level does the esophagus pass through the diaphragm?
T10
** is also the level at which you find the inferior extent of the lungs posteriorly **
At what vertebral level does the aorta pass through the diaphragm?
T12
** is also the level at which you’ll find the posterior extent of the parietal pleura **
At what vertebral level is the apex of the lungs found?
T1
At what vertebral level is the sternoclavicular joint located?
T2
At what vertebral level is the top of the aortic arch located?
T3
Around what vertebral level would you find the vifurcation of the trachea & sternal angle?
T4/5
At what vertebral level is the top of the heart located at?
T5
At what vertebral level would you expect to find the center of the roots of the lungs?
T6
At what vertebral level is the inferior angle of the scapula, xiphoid process, and the inferior extend of lungs anteriorly at the midclavicular line located?
T9
At what vertebral level would you expect to find the attachment of the crura of the diaphragm?
L3
What is the best modality to order to look at function: stroke volume?
MR or CT - 4 stars
Echo and Nuclear - 2 stars
What is the best modality to order to look at function: ejection fraction?
Nuclear, MR, or CT - 4 stars
Echo - 2 stars
What is the best modality to order to look at function: regional fraction?
MR or CT - 4 stars
Echo - 3 stars
Nuclear - 2 stars
What is the best modality to order to look at function: diastolic function?
Echo
CMR also, but not as good as Echo
(CANNOT use Nuclear or CT)
What is the best modality to order to look at function: valve function?
Echo
cannot use Nuclear
What is the best modality to order to look at function: coronary flow?
Nuclear
cannot use Echo or CT
What is the best modality to order to look at function: muscle perfusion?
Nuclear or MR - 4 stars
Echo and CT - 1 star
Of the 4 imaging modalities, echo, nuclear, CMR, or CT, which is the most available, and thus has the highest rated practicality?
Echocardiography
- Nuclear is next available, and thus practical
- CMR and CT least available, and thus practical
Of the 4 imaging modalities, echo, nuclear, CMR, or CT, which is the most portable?
Echocardiography
- Nuclear, CMR, and CT are not portable
Of the 4 imaging modalities, echo, nuclear, CMR, or CT, which has the highest radiation exposure to the patient?
CT (computed tomography) –> is the most
- Nuclear Cardiology is the second most.
- Echocardiography and CMR do not expose patients to radiation.
Of the 4 imaging modalities, echo, nuclear, CMR, or CT, which is the most expensive?
CMR and CT
- Echo is the least expensive and Nuclear is inbetween CMR and CT, and Echocardiography
Of the 4 imaging modalities, echo, nuclear, CMR, or CT, which is the least expensive option to order for imaging?
Echocardiography
** CMR and CT are the most expensive to order for imaging studies
What is the best imaging modality to order if looking at structure: cardiac anatomy?
CMR or CT - 4 stars
Echo - 2 stars
Nuclear - not used to look at anatomy structures
What is the best imaging modality to order if looking at structure: heart chamber size?
CMR or CT - 4 stars
Echocardiography - 3 stars
Nuclear - 1 star
What is the best imaging modality to order if looking at structure: muscle thickness?
CMR or CT - 4 stars
Echocardiography - 3 stars
What is the best imaging modality to order if looking at structure: valve structure?
Echocardiography - 4 stars
CMR and CT - 2 stars
What is the best imaging modality to order if looking at structure: coronary arteries?
CT - 4 stars
CMR - 2 stars
Echo and Nuclear not good at all for imaging coronary arteries
What is the best imaging modality to order if looking at structure: pericardium?
CT - 4 stars
CMR and Echo - 3 stars
Nuclear - not good for imaging pericardium
For what imaging would it be best to order an echocardiogram?
Structure:
- valve structure
Function:
- diastolic function
- valve function
Practicality:
- availability
- portability
- cost
- no radiation exposure
Which cardiac structure would echocardiography imaging be most suited to order?
Valve Structure
Which cardiac function would echocardiography imaging be most suited to order for?
- Diastolic Function
- Valve Function
True or False:
Both CT and MRI are used for chest studies, although CT is more common.
True
** but, MRI is used for some heart studies and in cases in which patients may have allergies or other problems with receiving iodinated contrast used in CT!
What is the best way to see blood in the heart on MR imaging?
By using Gadolinium Contrast injections. Addition of the gadolinium contrast really turns the blood much more white in imaging. This is much better than trying to decide between T1 or T2 weighted because then you have to determine if the blood is flowing slower, faster, and also how protein rich the fluid may be.
True or False:
Air appears as a gray color on CT imaging.
FALSE –> on CT, air is solid black.
** thus, use the solid black of the trachea to orient yourself on CT imaging! **
Upon reviewing a plain film PA view you note increased opacity in the left lung with an apparent meniscus sign, which confirms pleural effusion. What causes the meniscus sign?
A) the patient was not inhaling when the image was taken
B) The patient was turned obliquely
C) Surface tension of fluid on pleura
D) Additional effusion in the lung parenchyma
C) Surface Tension of Fluid on Pleura
An 81 year old male patient presents with reduced lung volume and crepitus upon inhalation in the right thorax. Given the patients age and limited mobility you request PA plain film x-ray. Upon reviewing the film the right side shift of the heart suggests and error in image production, but proper method is confirmed. What condition accounts for this result?
A) patient was not inhaling when the image was taken
B) the patient was turned obliquely
C) patients has a patent foramen ovalis
D) patient has situs inversus
D. The patient has situs inversus
A 45 year old male patient presents with a severe cough, which arose after a rapid hike in Leadville, CO. You suspect the cough is a consequence of interstitial pulmonary edema, a symptom of altitude sickness. Your diagnosis is confirmed when you identify which of the following in a plain film x-ray?
A. Kerley B lines
B. Meniscus sign
C. Kelley A lines
D. Scotty dog sign
A. Kerley B lines
B lines show up near the periphery.
A lines show up near the center, near the hila.
What is the definition of Vasculogenesis?
The formation of new vascular channels by assembly of individual cell precursors called angioblasts.
** from mesoderm
What is the definition of Angiogenesis?
The development of blood vessels from pre-existing vessels.
During which week of development does vasculogenesis begin?
End of Week 3
At what week of development is the first aortic arch formed?
Week 4
What embryonic cell type(s) derivatives are supplied by ventral segmental arteries?
> splanchnic layer of lateral plate mesoderm
> endoderm
What embryonic cell type(s) derivatives are supplied by lateral segmental arteries?
> intermediate mesoderm derivatives
Example:
- renal arteries
- blood supply to suprarenals
- ovarian/testicular arteries to gonads
What embryonic cell type(s) derivatives are supplied by dorsal segmental arteries?
> supply derivatives of somites
Example:
- posterior intercostal arteries
- lumbar arteries in abdomen
- muscular of the body wall
During which days of development are the formation of rudiments of the remaining aortic arches (2-6) formed?
Days 26-32
During which days of development does the completion of aortic arch development occur?
Days 32-37
During development of the aortic arches, where are the majority of the branches given off to?
Developing Head
send lots of branches to developing head because the developing brain tissues need lots of oxygen and nutrients
What are the derivatives of the 1st aortic arch?
> external carotid
> maxillary
What are the derivatives of the 2nd aortic arch?
> stems of stapedial arteries
What are the derivatives of the aortic sac?
> brachiocephalic artery
> base of arch of aorta
What are the derivatives of the 3rd aortic arch?
> common carotid
> internal carotid
What are the derivatives of the 4th aortic arch?
> Left: medial portion of arch of aorta
> Right: proximal right subclavian artery
What are the derivatives of the 6th aortic arch?
Pulmonary Arteries:
> Left - distal ductus arteriosus
> Right - distal degenerates
What are the derivatives of the 5th aortic arch?
Trick - there’s NOT a 5th aortic arch in humans
Which aortic arch gives rise to the pulmonary blood supply?
6th Aortic Arch
What are the derivatives of the 7th intersegmental arteries?
Right - distal part of right subclavian artery
Left - entire left subclavian artery
What are the derivatives of the dorsal aorta?
Right - portion of right subclavian artery
Left - descending aorta
Which 2 aortic arches give rise to the right subclavian artery?
> Distal Portion - right 7th intersegmental artery
> Proximal Portion - right 4th aortic arch
Which aortic arch does the right and left recurrent laryngeal nerves loop around?
> 6th Aortic Arch
Why does the right recurrent laryngeal nerve take a different course than the left recurrent laryngeal nerve?
> because the right 6th aortic arch degenerates and the nerve migrates up around the proximal portion of the right subclavian artery, which is a derivative from the 4th aortic arch.
> the left 6th aortic arch gives rise to the ductus arteriosus, which becomes the ligamentum arteriosum.
Through which artery is oxygenated blood from the left umbilical vein diverted around the liver and dumps into the inferior vena cava?
Ductus venosus
The ductus arteriosus must close within 72 hours after birth. What cause this?
Increased oxygen leads to decreased prostaglandins & increased bradykinin, which causes closure. It becomes the ligamentum arteriosum.
What type of shunt is caused by a persistent ductus arteriosus?
Left-to-Right, which is Acyanotic
- high pressure blood in aorta goes into pulmonary truck
- can destroy capillary beds in lungs
The persistence of what vessel during development leads to a double aortic arch?
Persistence of Distal Portion of the Right Dorsal Aorta.
**forms a vascular ring around the trachea and esophagus
What are the presenting symptoms of a double aortic arch pathology?
> stridor > respiratory infections > respiratory distress > wheezing > cough > esophageal complaints are also common, including: - dysphagia - feeding difficulty - vomiting
The obliteration of which aortic arch arteries cause an interrupted aortic arch pathology?
> both right and left 4th aortic arch arteries are obliterated
distal right dorsal aorta is retained
left 4th arch - left medial portion of aortic arch
right 4th arch - proximal right subclavian artery
What happens during development that causes an abnormal origin of the right subclavian artery?
> the right 4th aortic arch and the proximal part of the right dorsal aorta obliterate
> the right subclavian artery passes behind the esophagus and trachea
What pathology is seen on imaging when the right subclavian artery passes behind the esophagus and trachea?
Abnormal origin of right subclavian artery, which is caused by the obliteration of the right 4th aortic arch and proximal part of right dorsal aorta.
** patient has decreased BP in Rt. upper limb compared to the rest of the body
What developmentally causes a right aortic arch?
Left 4th Aortic Arch and Left Dorsal Aorta are Obliterated and replaced by the corresponding vessels on the right side.
If ligamentum arteriosum lies on the left side and passes behind the esophagus, swallowing can be affected.
** right aortic arch pathology is typically asymptomatic
During which weeks of development does remodeling of the inflow of the heart occur?
Weeks 4-8
What are the 4 inflow vessels of the heart that are remodeled during weeks 4-8 of development?
> sinus venosus
cardinals (anterior, posterior, and common)
vitelline
umbilical
What does the Vitelline V. proximal to the heart turn into?
> left vein - degenerates
> right vein - inferior vena cava
What doe the Vitelline V. within the liver turn into?
> right - forms hepatic vein (part of inf. vena cava)
> Rt. and Lf. form portal vein (from gut)
What is the fate of the right umbilical vein during remodeling from 4-8 weeks?
degernerates entirely
What is the fate of the left umbilical vein during remodeling from 4-8 weeks?
> proximal degenerates
within liver - forms ductus venosus
distal persists in embryo providing placental return (which is rich in oxygen)
What does the Right Anterior Cardinal Vein turn into?
> internal jugular
> superior vena cava
What does the Left Anterior Cardinal Vein turn into?
> left brachiocephalic trunk
What area is drained by the anterior cardinal vein?
drainage from cranial territory
What area is drained by the posterior cardinal vein?
drainage from body wall
What is the posterior cardinal vein replaced by?
> subcardinal vein
> supracardinal vein
What does the posterior cardinal vein turn into?
posterior system degenerates except for root of azygos and common iliac veins
What error during development results in a left superior vena cava pathology?
persistence of Left Anterior Cardinal Vein and Obliteration of the Common Cardinal and Proximal Part of the Anterior Cardinal Veins on the Right
What pathology is caused by persistence of the left anterior cardinal vein and obliteration of the common cardinal and proximal part of the anterior cardinal veins on the right?
Left Superior Vena Cava
What error during development results in a double superior vena cava pathology?
persistence of the Left Anterior Cardinal Vein and failure of the Left Brachiocephalic Vein to form.
What pathology is caused by persistence of the left anterior cardinal vein and failure of the left brachiocephalic vein to form?
Double Superior Vena Cava
List the 4 veins that contribute to inferior vena cava formation.
> right vitelline/hepatic veins and sinuses (hepatic)
right subcardinal vein (pre-renal)
subcardinal-supracardinal anastomosis (renal)
right supracardinal vein (postrenal)
What vein composes the hepatic segment of the inferior vena cava during remodeling from 4-8 weeks of development?
> Rt. Vitelline/Hepatic Vs. & Sinuses
What vein composes the pre-renal segment of the inferior vena cava during remodeling during weeks 4-8 of development?
> Rt. Subcardinal V.
What vein composes the renal segment of the inferior vena cava during remodeling during weeks 4-8 of development?
> Subcardinal-Supracardinal Anastomosis
What vein composes the post-renal segment of the inferior vena cava during remodeling during weeks 4-8 of development?
> Rt. Supracardinal
Persistence of which vein during remodeling during weeks 4-8 of development causes a malformation of the inferior vena cava?
Sacrocardinal V.
anastomotic connections persisted instead of remodeling and degenerating
The distal portion of which aortic arch gives rise to the ductus arteriosus?
6th Aortic Arch
What are the 4 main arteries that the dorsal aortae gives rise to during remodeling?
> Ventral Segmental aa.
Umbilical aa.
Lateral Segmental aa.
Dorsal Intersegmental aa.
What arteries arise from the ventral segmental aa. during remodeling?
> celiac a.
superior mesenteric a.
inferior mesenteric a.
What does the umbilical aa. give rise to during remodeling?
> medial umbilical folds
What arteries arise from the lateral segmental aa. during remodeling?
> renal aa.
testicular or ovarian aa.
middle suprarenal aa.
phrenic aa.
What arteries arise from the dorsal intersegmental aa. during remodeling?
> vertebral aa.
posterior intercostal aa.
lumbar aa.
Is a right-to-left shunt classified as an cyanotic or acyanotic pathology?
Cyanotic
Is a left-to-right shunt classified as a cyanotic or acyanotic pathology?
Acyanotic
During which week of development does the heart being to develop?
mid 3rd week
Which week of development does circulation begin?
4th week
Which week of development does the heart begin to beat?
4th week (day 22)
What tissue types is the heart derived from?
> splanchnic portion of lateral plate mesoderm
mesenchyme (neural crest cells - form aorticopulmonary septum)
angioblastic tissue
What does the primary heart fields (cardiogenic cord) develop into?
> left and right atria
left ventricle
most of right ventricle
What does the secondary heart fields develop into?
> right ventricle
> outflow tract (bulbus cordis + runchus arteriosus)
Which heart fields develop into the right ventricle and outflow tract?
secondary heart fields
Which heart fields develop into the left and right atria, left ventricle, and most of the right ventricle?
primary heart fields (aka Cardiogenic Cord)
What 2 structures compose the outflow tract?
> bulbus cordis
> truncus arteriosus
What embryonic tissue type is the endocardium, myocardium, and epicardium derived from?
Splanchnic portion of lateral plate mesoderm
Which layer of the heart is the internal endothelial lining?
endocardium (from splanchnic mesoderm)
Which layer of the heart is the muscular wall?
myocardium (from splanchnic mesoderm)
Which layer of the heart is the outer covering of the heart (visceral pericardium)?
epicardium (from splanchnic mesoderm)
Is the endocardium, myocardium, or epicardium the same as the visceral pericardium?
Epicardium = Visceral Pericardium
What embryonic structure turns into the transverse sinus?
Dorsal Mesocardium
What does the dorsal mesocardium give rise to once it degenerates during development?
transvers sinus
Through which pharyngeal arches do neural crest cells migrate through from their origination in the telencephalon on their way to participate in cardiac development?
Pharyngeal Arches 3, 4, and 6.
Neural crest cells migrate through pharyngeal arches 3, 4, and 5 from their origination in the myelencephalon to participate in the formation of what?
> Aorticopulmonary Septa
truncus arteriosus
bulbus cordis
True or False:
Retinoic acid, Hos genes, Nf-1, and Pax 3 regulate cardiac neural crest migration and differentiation?
True
What are the 5 primitive divisions of the fused endocardial heart tubes?
> truncus arteriosus > bulbus cordis > ventricle > atrium > sinus venosus
What forms the bulboventricular loop?
> bulbus cordis
> ventricles
In which direction does the bulboventricular loop bend during development, left or right?
Bulboventricular Loop - bends to the right
** the bulbus cordis and ventricles grow quickly, causing the heart to bend on itself, to the right
** the atrium and sinus venosus come to lie dorsally (in back) because the ventricle moves down asthe bulboventriuclar loop bends to the right.
During development, what is the cause of dextrocardia?
Bulboventricular Loop - bends to the left, which causes a complete mirrored heart from normal to develop.
** bulboventricular loop normall bends to the right
In what situation would dextrocardia cause no problem to the patient?
If Dextrocardia occurs with Sinus Inversus (abdominal organs reversed) then there’s no problem to patient.
** if dextrocardia occurs in isolation then typically associated with other congenital problems
The fusion of what structure(s) results in formation of the Right and Left Atrioventricular Canals, separating atria from ventricle?
Endocardial (AV) Cushions growing together.
What are endocardial (AV) cushions derived from?
mesodermal growth from the dorsal and ventral walls
mesenchyme invades during the 5th week of development
During which week of development does the mesenchyme, which makes up the endocardial (AV) cushions, invade?
during 5th week of development
What signaling molecule is formation remodeling of the AV cushions dependent on?
Retinoic Acid Dependent.
What pathology does disruption of retinoid signaling result in?
AV canal defects
** too much retinoic acid = AV canal defects
What are the 2 septums of the atrium during development?
> Septum primum
> Septum secundum
What are the 2 foramen of the septum primum?
> Foramen primum
> Foramen secundum
What is the foramen primum a shunt between?
right and left atrium
What does the formation of the foramen secundum ensure?
shunting
The septum secundum overlaps the eptum primum and has what foramen in it?
Foramen Ovale
Which foramen is gone when it fuses with the endocardial cushions?
Foramen primum
The foramen secundum forms before what foramen disappears when it fuses with endocardial cushions?
Foramen primum
What fetal separation of the atria does not completely close during development, leaving a patent foramen ovale?
Septum secundum
During embryonic and fetal life, blood entering the right atrium passes to the left atrium via the forament ovale and what?
Ostium Secundum
** passes to left atrium via the foramen ovale and ostium secundum!!
What is the valve of the oval foramen derived from?
Septum primum
True or False:
The muscular portion of the interventricular septum completely fuses with the endocardial cushion.
FALSE - the muscular portion of the interventricular septum does not fuse with the endocardial cushion, forming an interventricular foramen.
What does the aorticopulmonary septum divide the bulbus cordis and truncus arteriosus into?
Ascending Aorta and the Pulmonary Trunk
- aorticopulmonary septum then fuses with the endocardial cushion
What is the right bulbus cordis incorporated into during development?
> conus arteriosus (infundibulum)
formed by bulbus cordis incorporation into the right ventricle
What is the left bulbus cordis incorporated into during development?
> aortic vestibule (formed by incorporation of bulbus arteriosus into left ventricle)
True or False:
Neural crest cells associated with pharyngeal arches 4 and 6 migrate into the truncus arteriosus (undivided outflow tract) and bulbus cordis (aka conus cordis).
True
> neural crest cells form:
- bulbar ridges
- truncal ridges
once the ridges form and spiral 180 degrees, the aorticopulmonary septum is formed
What 3 structures make up the membranous interventricular septum?
> endocardial cushion
right bulbar ridge
left bulbar ridge
What embryonic tissue type is the endocardial cushion derived from?
Splanchnic Mesoderm
What embryonic tissue type are the right and left bulbar ridges derived from?
neural crest cells
Complete fushion of the endocardial cushion, right bulbar ridge, and left bulbar ridge, which all 3 make up the membranous interventricular septum, results in what?
disappearance (closure) of the interventricular foramen
Defects in the interventricular septum are due to the membranous part of muscular part?
Membranous part of the Interventricular Septum, which is typically due to the neural crest cells making up the left and right bulbar ridges.
- which consists of the:
- endocardial cushion
- right bulbar ridge
- left bulbar ridge
What cardiac valve begins development once partition of the truncus arteriosus is nearly complete?
Semilunar Valve
Between what two structures that compose the outflow tract does the semilunar valve develop between?
> bulbus cordis and truncus arteriosus
The disruption of what can result in aortic or pulmonary valve defects?
Disruption of Neural Crest that contribute to the truncoconal cushions can result in aortic or pulmonary valve defects.
What gives rise to most of our tribuspid and bicuspid valves?
Endocardial Cushions
The dorsal and ventral valve swellings are derived from what embryonic tissue type?
splanchnic mesoderm
** left and right bulbar ridges derived from neural crest cells
