Superior Mediastinum and Heart (CVR) Flashcards
What does the mediastinum contain
Heart and pericardium
Great vessels
The veins that drain the chest wall
The trachea an main bronchi
The esophagus
Nerves
Lymphatics
Where is the line that splits the superior and inferior mediastinum
From the sternal angle to the T4/T5 junction
Main components of the Superior Mediastinum
Arch of aorta
Superior vena cava
trachea
oesophagus
phrenic nerves and vagus nerves
thoracic duct
thymus gland
Where does the arch of the aorta lie
In the superior mediastinum
Where does the descending aorta lie
Posterior mediastinum
What Does ABCS stand for in the aortic arch
Aorta
Braciocephalic artery
Common carotid artery
Subclavian Artery
What is the ligamentum arteriosum a remenent of from being a foetus
Ductus arteriosus
What does the Ligamentum arteriosus connect together
Pulmonary trunk and aortic arch
Where would blood have travelled from and to in the ductus arteriosus
From the Pulmonary trunk to the aortic arch
Where does the superior vena cava return blood from
Head neck and upper limbs
What two veins join together to form the superior vena cava
Left and right braciocephalic veins
Where does the SVC lie
superior mediastinum
What is each brachiocephalic vein made up of
Subclavian and Internal Jugular veins
Where does the IVC return blood from
Returns blood to heart from all regions inferior to diaphragm
Where does the Trachea bifurcate
Sternal angle, which is the T4/T5 junction
Where does the oesophagus extend to and from
Pharynx (midline of neck) to stomach
Where is the oesophagus in the mediastinum
Midline of thorax and posterior to Trachea
What nerve fibers are the phrenic nerves formed by
C3, C4 and C5
What two blood vessels do the vagus nerves run alongside in the neck
Internal carotid artery and internal jugular vein
What do the Vagus nerves give rise to
Recurrent laryngeal nerve
What structure of the heart does the left recurrent laryngeal nerve loops under? where does it go after
Loops under the arch of the aorta
Travels to the left side of the neck
What artery does the right recurrent laryngeal nerve descend alongide
Right subclavian artery
What does the right recurrent laryngeal nerve loop under
Right subclavian artery
Where does the right recurrent laryngeal nerve run between when ascending
Trachea and oesophagus
What is the pericardium
A tough fibrous sac that encloses the heart
Two layers of the pericardium
Fibrous (thick outer) and Serous layer (thin inner layer)
What is the Serous layer of the pericardium made up of
The parietal (outer) and visceral layer (inner)
What nerve innervates the fibrous pericardium
Phrenic nerves
Where is the apex of the heart located and what is it formed by?
Left 5th intercostal space in the midclavicular line
Where does the right border of the heart extend to and from
Right 3rd costal cartilage to right 6th costal cartilage
Where does the left border of the heart extend to and from
left 2nd intercostal space to the left 5th intercostal space in the midclavicular line
What does the right coronary artery supply
SA node and AVN node
What does the right marginal artery supply
Inferior border of the heart
What does the posterior interventricular artery supply? on What border of the heart
Both ventricles and on the inferior surface of the heart
Two main branches of the Left coronary artery
Left anterior descending artery
Circumflex artery
What is a sulcus
Grooves in the external surface of the heart which contains arteries and veins
What sulcus does the LAD run in
The anterior interventricular sulcus
What does the LAD supply
Both ventricles
What surface does the circumflex artery travel on to
Inferior/diaphgramic
Where does the left marginal artery arise from and what does it supply
arises from circumflex and supplies the left ventricle
What is the fossa ovalis
Depression in interatrial septum
What is the Crista Terminalis? Where are they found?
Muscular ridge that seperates smooth walled posterior part of the atrium from the anterior part
Found in atria
What are the ridges called on the anterior part of the atria?
Pectinate muscles
What 5 features does the right ventricle contain?
Interventricular septum
Trabeculae carneae
Papillary muscles
Chordae tendinae
Moderator band
What are the trabeculae carneae?
Muscular ridges on the internal wall of ventricles
What are the papillary muscles?
Projections of the trabeculae carneae
What are Chordae Tendineae?
Fibrous cords that connect papillary muscles to tricuspid valve
What does The pulmonary trunk split into when it exits the right Ventricle?
Left and right Pulmonary arteries
Does the Left atrium (like the right atrium) also have a smooth-walled posterior part and rough anterior part?
Yes
What valve is found between the left atrium and left ventricle? Which valve is found between the right atrium and right ventricle?
Left- Mitral valve
Right- Tricuspid valve
What is the function of the papillary muscles?
Contract and tense the chordae tendineae as the ventricle contracts preventing them everting into the atria
How many cusps does each semilunar valve have?
Three
What forms inbetween the free edge of the semilunar cusp and the vessel wall?
Sinuses
What are the causes the sounds of the heart when auscultated?
Heart valves closing
Where are the Aortic and pulmonary auscultatory areas?
Aortic= 2nd intercostal space (right to sternum)
Pulmonary= 2nd intercostal space (left to sternum)
Auscultatory areas for the Tricuspid and Mitral valve?
Tricuspid= 5th intercostal space (left to sternum)
Mitral= 5th intercostal space= left midclavicular line
Where is the Sinoatrial node located?
Superior end of crista terminalis (in the right atrium)
Where is the Atrioventricular node located?
Inferior end of of the interatrial septum
What fibres arise from the AV node? What do they divide into?
Atrioventricular bundle
Left and right bundle branches
What do the Bundle branches give rise to in the conducting system? What do these fibres enter?
Give rise to Purkinje fibres
Enter the right and left ventricles
What arteries supply the SA node? What proportion of people are supplied by each artery?
Right coronary artery and Left coronary artery
60% supplied by RCA
40% supplied by LCA
What artery supplies the AV node?
Posterior interventricular artery
What artery supplies the Bundle of His?
Left Coronary Artery
Where do Visceral afferent fibres send information to and from?
From the heart back to the CNS
Where can heart pain be perceived from? What is this pain called?
Chest, Left side of neck and/or left arm
