Anatomy and Development of the Heart III

Question 1

The most common cyanotic heart defect

Answer 1

Tetralogy of Fallot (TOF)

Question 2

Caused by a malpositioning of the aorticopulmonary septum

-the cyanosis frequently appears sometime after birth

Answer 2

TOF

Question 3

In TOF, the aorticopulmonary septum forms in a displaced fashion toward the

Answer 3

Pulmonary side of the truncus arteriosus and conus cordis

Question 4

This displacement is toward the right side of circulation, which means it is called

Answer 4

Dextrapositioning

Question 5

The pulmonary trunk is anatomically anterior and to the left of the

Answer 5

Ascending aorta

Question 6

The dextrapositioning of the aorticopulmonary septum in TOF results in

Answer 6

1. ) Pulmonary stenosis
2. ) Overriding aorta
3. ) Ventricular septal defect

Question 7

The aorta is abnormally wide and overrides both ventricles

Answer 7

Overriding aorta

Question 8

Secondary to the major structural defects seen in TOF, we also see

Answer 8

Right ventricular hypertrophy

Question 9

Because of the pulmonary stenosis, the pressure in the right ventricle is elevated causing right ventricular blood to shunt through the VSD into the overriding aorta. This right to left shunt results in

Answer 9

Cyanosis

Question 10

When the aorticopulmonary septum does not form, the truncus arteriosus does not become the

Answer 10

Ascending aorta and pulmonary trunk (Persistent Truncus Arteriosus)

Question 11

In persisten truncus arteriosus, both ventricles empty their blood into the same artery, thus oxygenated and deoxygenated blood are mixed and we see

Answer 11

Cyanosis

Question 12

Because the absent aorticopulmonary septum would have contributed to the membranous ventricular septum, persistent truncus arteriosus is accompanied by

Answer 12

VSD

Question 13

This defect is the most common cause of cyanosis presenting immediately at birth

Answer 13

Transposition of the great arteries

Question 14

In the transposition of the great arteries, the aorticopulmonary septum, which normally forms in a spiral shape is not

Answer 14

Spiraled

Question 15

What affect does the lack of spiraling have on the positioning of the aorta and pulmonary trunk?

Answer 15

Their positions are reversed

i.e. right ventricle flows to aorta instead of pulmonary trunk

Question 16

Septal defects are common and PDA is typically seen in infants with

Answer 16

Transposition

Question 17

The region within the thoracic cavity between the two pleural spaces

Answer 17

Meiastinum

Question 18

What are the following borders of the mediastinum?

1. ) Superior
2. ) Inferior
3. ) Anterior

Answer 18

1. ) Thoracic inlet
2. ) Diaphragm
3. ) Sternum

Question 19

What are the following borders of the mediastinum?

1. ) Posterior
2. ) Lateral

Answer 19

1. ) Vertebral column

2. ) Mediastinal Pleura

Question 20

The mediastinum is arbitrarily divided into a superior and inferior region by an imaginary horizontal plane at the level of

Answer 20

T4

Question 21

Where does this plane interset

1. ) Posteriorly
2. ) Anteriorly

Answer 21

1. ) Bottom of T4 vertebra

2. ) Manubriosternal junction (sternal angle)

Question 22

Within the mediastinum this plane is at the level of

the

Answer 22

Tracheal bifurcation

Question 23

The region above this plane is the

Answer 23

Superior mediastinum

Question 24

The region below this plane is divided into which three regions?

Answer 24

1. ) Middle mediastinum
2. ) Anterior mediastinum
3. ) Posterior mediastinum

Question 25

The fibrous pericardium and everything within it comprise the

Answer 25

Middle mediastinum

Question 26

Between the pericardium and sternum is the

Answer 26

Anterior mediastinum

Question 27

Between the pericardium and the vertebral column is the

Answer 27

Posterior mediastinum

Question 28

The structures in the superior mediastinum may be considered in layers. From posterior to anterior the 5 layers are:

Answer 28

1. ) Digestive layer 2. ) Respiratory layer 3. ) Arterial Layer 4. ) Venous layer 5. ) Glandular layer

Question 29

The digestive layer is made up of the

Answer 29

Esophagus

Question 30

The respiratory layer is made up of the

Answer 30

Trachea

Question 31

Bifurcates at T4 and therefore does not descend below the superior mediastinum

Answer 31

Trachea

Question 32

The arterial layer is made up of the

Answer 32

1. ) aortic arch and its branches 2. ) distal ascending aorta 3. ) proximal descending aorta

Question 33

What are the 3 branches of the aortic arch?

Answer 33

1. ) Brachiocephalic trunk 2. ) Left common carotid artery 3. ) Left subclavian artery

Question 34

The venous layer is made up of the

Answer 34

SVC and its tributaries: the right and left brachiocephalic veins

Question 35

Formed by the union of the internal jugular and subclavian veins

Answer 35

Brachiocephalic veins

Question 36

Has a vertical course in line with the SVC

Answer 36

The right brachiocephalic vein

Question 37

Has an oblique course downward and to the right across the midline

Answer 37

The left brachiocephalic vein

Question 38

The glandular layer is made up of the

Answer 38

Thymus

Question 39

Enters the superior mediastinum with the left common carotid artery

Answer 39

Left vagus nerve

Question 40

The left vagus nerve passes anterior to the aortic arch and gives off the

Answer 40

Left recurrent laryngeal nerve

Question 41

Passes under the aortic arch distal to the ligamentum arteriosum

Answer 41

Left recurrent laryngeal nerve

Question 42

Enters the superior mediastinum after already having given off the right recurrent laryngeal nerve in the neck

Answer 42

Right vagus nerve

Question 43

Passes under the right subclavian artery and courses upward to the larynx -never in the mediastinum

Answer 43

Right recurrent laryngeal nerve

Question 44

The descending aorta, thoracic duct, azygos vein, hemiazygous vein, esophagus, vagus nerves and sympathetic trunks are all located in the

Answer 44

Posterior mediastinum

Question 45

Enters the posterior mediastinum to the left of the esophagus and gradually moves behind the esophagus as they descend

Answer 45

Descending aorta

Question 46

In the inferior part of the posterior mediastinum, the aorta is posterior to the

Answer 46

Esophagus

Question 47

Arises below the diaphragm as the cisterna chyli and ascends from the diaphragm in a vertical course slightly to the right of the midline

Answer 47

Thoracic Duct

Question 48

The thoracic duct shifts to the left and continues its vertical ascent to the left of the midline at about the

Answer 48

T6 level

Question 49

The thoracic duct drains into the junction of the

Answer 49

Left subclavian and internal jugular veins

Question 50

The only significant structure in the anterior mediastinum is the

Answer 50

Inferior portion of the thymus

Question 51

The diaphragm is composed of a

Answer 51

Muscular portion and a central tendon

Question 52

Dome shaped and upon contraction of its muscular portion it descends

Answer 52

Diaphragm

Question 53

The diaphragm is innervated by the

Answer 53

Phrenic nerve (C3-C5)

Question 54

The lumbar portion of the diaphragm has which three region of origin?

Answer 54

1. ) Lumbar origin 2. ) Costal origin 3. ) Sternal origin

Question 55

The lumbar origin is comprised of three things, what are they?

Answer 55

1. ) 2 crura 2. ) Medial arcuate ligament 3. ) Lateral arcuate ligament

Question 56

A thickening of the deep fascia covering the anterior surface of the psoas major

Answer 56

Medial arcuate ligament

Question 57

A thickening of the deep fascia covering the anterior | surface of the quadratus lumborum

Answer 57

Lateral arcuate ligament

Question 58

Diaphragm muscle fibers that originate from the inner surfaces of the lower 6 ribs are said to be part of the

Answer 58

Costal origin

Question 59

Muscle fibers of the diaphragm arising from the inner surface of the xyphoid process are part of the

Answer 59

Sternal origin

Question 60

What are 4 aperatures in the diaphragm?

Answer 60

1. ) Caval Hiatus (T8) 2. ) Esophageal Hiatus (T10) 3. ) Aortic Hiatus (T12) 4. ) Sternocostal Hiatus (T10)

Question 61

Transmits the IVC and some branches of the right phrenic nerve -within the central tendon to the right of the midline

Answer 61

Caval Hiatus

Question 62

Transmits the esophagus and the anterior and posterior vagus nerves -within the muscle of the right crus to the left of the midline

Answer 62

Esophageal hiatus

Question 63

The skeletal muscle of the right crus serves as a sphincter for the

Answer 63

Esophagus

Question 64

Transmits the aorta, the azygos vein, and the thoracic duct -behind the two crura in the midline

Answer 64

Aortic Hiatus

Question 65

Transmits the superior epigastric vessels -between the muscle of the sternal origin and the costal origin

Answer 65

Sternocostal Hiatuses

Question 66

The sympathetic trunk, the thoracic splanchnic nerves, the hemiazygos vein and most branches of the phrenic nerves pass through the diaphragm without a specific

Answer 66

Hiatus

Question 67

Any muscle that has one of its attachments on the ribs can assist with

Answer 67

Inspiration

Question 68

``` Because the innervation to the diaphragm (motor and sensory) is primarily from C3-5, pain arising from the diaphragm (e.g. subphrenic abscess) is referred to these dermatomes in the ```

Answer 68

Shoulder region

Question 69

What is an important landmark at T2?

Answer 69

Jugular notch

Question 70

What is an important landmark at T3?

Answer 70

Base of scapular spine and top of aortic arch

Question 71

What is an important landmark at T7?

Answer 71

Inferior angle of scapula

Question 72

What is an important landmark at T8?

Answer 72

Caval Hiatus

Question 73

What is an important landmark at T9?

Answer 73

Xyphoid process

Question 74

What is an important landmark at T10?

Answer 74

Esophageal Hiatus

Question 75

What is an important landmark at T12?

Answer 75

Aortic Hiatus

Question 76

The Sternal angle, second costal cartilage, tracheal bifurcation, and upper end of the ascending aorta are located at

Answer 76

T4