Anatomy of the CVS (Thorax 2) Flashcards
What are the three divisions of the inferior mediastinum?
Anterior, middle and posterior
What are the main contents of the superior mediastinum?
Thymus gland, brachiocephalic veins, SVC, aortic arch, vagus nerve, phrenic nerve, trachea, oesophagus and thoracic duct
What are the main contents of the posterior mediastinum?
Oesophagus, vagus nerve, azygous vein, sympathetic trunk, thoracic duct, descending aorta and splanchnic nerve
Where does the cephalic vein run and where does it drain?
It runs up the lateral side of the arm and drains into the axillary vein
Where does the basilic vein run and which veins does it join with?
It runs up the arm on the medial side and becomes continuous with the brachial veins
What connects the basilic and cephalic veins?
The median cubital
Where does the median cubital lie?
Across the cubital fossa
Where does the long saphenous vein run and where does it drain?
It travels up the leg medially and drains into the femoral
Where does the short saphenous vein run and where does it drain?
It travels up the lower leg posteriorly and drains into the popliteal
What does the popliteal become proximally?
The femoral vein
What does the femoral become proximally?
The external iliac vein
Where does the subclavian artery arise from?
The aortic arch
Where does the subclavian artery become the axillary artery?
At the lateral border of the 1st rib
Where does the axillary artery become the brachial artery?
At the inferior border of the teres major muscle
Where does the brachial artery divide into the radial and ulnar arteries?
The cubital fossa
What artery does the external iliac become in the anterior thigh?
The common femoral
What branches does the common femoral give off?
The superficial and deep femoral arteries
Where does the superficial femoral become the popliteal?
In the popliteal fossa
What artery does the posterior tibial artery give off?
Fibular artery
What artery does the anterior tibial artery become?
The dorsalis pedis
What are the layers of a blood vessel wall from inner to outer?
Tunica intima, tunica media and tunica adventitia
What is the tunica intima composed of?
A single layer of endothelial cells and a small amount of subendothelial connective tissue
What separates the tunica intima from the tunica media?
The internal elastic lamina - a dense elastic membrane
What is the tunica media composed of?
Smooth muscle, elastic fibres and connective tissue
What is the function of the tunica media?
Structural support, vasoreactivity and elasticity
What separates the tunica media from the tunica adventitia?
The external elastic lamina
What is the tunica adventitia composed of?
Connective tissue, nutrient vessels (vaso vasorum) and autonomic nerves (nervi vasorum)
What are the main features of arteries?
A thick smooth muscular wall, a small lumen and a round appearance
What are the main features of veins?
A thin wall, less smooth muscle than an artery and a wide lumen
What are the main features of cardiac muscle?
Branching striated fibres, central rounded nuclei and intercalated discs
What are the features of muscular (distributing) arteries?
Thick smooth muscle in the wall and few elastic fibres
What are the features of elastic (conducting) arteries
Numerous laminae of dark staining, wavy, elastic fibres in the wall amongst the smooth muscle
Which part of the heart makes up the right border?
Right atrium and SVC
Which part of the heart makes up the left border?
Left ventricle and aortic arch
Which part of the heart makes up most of the anterior surface?
Right ventricle
What is cardiomegaly
Enlargement of the heart
What are the main features of the right atrium?
Openings for the SVC and IVC and coronary sinus, interatrial septum, fossa ovalis, musculi pectinate and the tricuspid valve
What are the main features of the right ventricle?
Tricuspid valve, chordae tendineae, papillary muscles, trabeculae carneae, moderator band, opening for pulmonary trunk and the interventricular septum
What are the main features of the left atrium?
Openings for the left and right superior and inferior pulmonary veins, Mitral valve and the chamber itself is small and smooth walled
What are the main features of the left ventricle?
Mitral valve, papillary muscles, chordae tendineae, trabeculae carneae, opening for the aorta, interventricular septum and a thick wall
Where does the right coronary artery arise from?
The right aortic sinus of the ascending aorta
Where does the right coronary artery run?
In the coronary (atrioventricular) sulcus
Which branch does the right coronary artery give off at the inferior border?
The right marginal artery
Which branch does the right coronary artery give off on the posterior surface of the heart?
The posterior interventricular artery
Where does the left coronary artery arise from?
The left aortic sinus of the ascending aorta
Where does the left coronary artery run?
In the coronary sulcus
What branches does the left coronary artery divide into almost immediately?
The anterior interventricular artery and the circumflex artery
What arteries form the two anastomoses?
Anterior and posterior descending
Circumflex and right coronary artery
Where do the great, middle and small cardiac veins drain?
The coronary sinus lying alongside the circumflex
Where does the coronary sinus drain into?
The right atrium
Where do the anterior cardiac veins drain into?
The right atrium
Which parts of the heart are innervated by the phrenic nerve?
The fibrous pericardium and the parietal layer of the serous pericardium - pain sensation
Which parts of the heart are innervated by the vagus nerve?
The heart itself and the visceral layer of the serous pericardium
Which parts of the heart are innervated by the sympathetic fibres?
The heart muscle and the visceral layer of the serous pericardium
Where do the internal signals of the heart arise from?
The sinoatrial node
Which bone forms the anterior border of the superior mediastinum?
Manubrium
Which vertebrae form the posterior border of the superior mediastinum?
T1-4
What plane separates the superior mediastinum from the inferior mediastinum?
The sterno-manubrial plane (transverse)
Which heart chamber forms the right border of the heart?
Right atrium
Which heart chamber forms the left border of the heart?
Left ventricle
Which heart chambers form the inferior border of the heart?
Left and right ventricles
Which heart chambers form the superior border of the heart?
Left and right atria
Which heart chamber forms the anterior/sternocostal surface of the heart?
Right ventricle
Which heart chamber forms the posterior surface/base of the heart?
Left atrium
Which heart chambers form the inferior/diaphragmatic surface of the heart?
Left and right ventricles
Posterior to which bone is the heart situated?
`Sternum
Anterior to which vertebrae is the heart situated?
T5-8
What structure does the inferior surface of the heart lie upon?
Central tendon of the diaphragm
At what vertebral level des the beginning and termination of the aortic arch occur?
T4
At what vertebral level does the bifurcation of the abdominal aorta occur?
L4
At what vertebral level do the common iliac arteries bifurcate?
L5
At which level do the external iliac arteries arise and what do they become?
They arise at T5 and become the femoral arteries
At what level do the internal iliac arteries arise and where do they supply?
They arise at T5 and supply the pelvic viscera
What are the tributaries of the SVC?
Left and right brachiocephalic veins and the azygous vein
What are the tributaries of the IVC?
Left and right common iliac veins
Which venous system drains blood from the posterior intercostal veins to SVC?
Azygos venous system
Where is the azygos vein found?
Immediately to the right of the descending thoracic aorta
At what vertebral level does the hemiazygos vein drain into the azygos vein?
T8/9
Which posterior chest wall arteries arise from the descending aorta?
Intercostal arteries
Which part of the spinal nerve are the intercostal nerves formed from?
Ventral ramus
Which artery is the origin of the internal thoracic artery?
Subclavian artery
Where is the thoracic duct located?
On the posterior thoracic wall between the azygos vein and the descending aorta
Where does the thoracic duct drain?
Into the medial end of the left subclavian vein
Where does the right lymphatic duct drain?
Into the medial end of the right subclavian vein
What is the cisterna chyli?
The most inferior part of the thoracic duct
Of the radial and ulnar arteries, which is the more superficial?
Radial artery
Of the radial and ulnar arteries which is the larger of the two?
Radial artery
Of what artery is the femoral artery a distal continuation?
External iliac artery
Where does the popliteal artery branch into the anterior and posterior tibial arteries?
Distal end of the popliteus muscle posterior to the tibia
Into which major vein does the great saphenous vein drain into?
Femoral vein
Into which major vein does the small saphenous vein drain into?
Popliteal vein?
Between which two layers of the heart wall does the pericardial cavity lie?
Between the epicardium (visceral serous pericardium) and the parietal serous pericardium
What type of cells make up the endocardium?
Simple squamous epithelium
What type of muscle makes up the myocardium?
Cardiac muscle
What type of cells make up the epicardium?
Simple squamous epithelium
Which layer belongs both to the heart wall and to the serous pericardium?
Epicardium
Which layer of the serous pericardium is inseparably attached to the inner surface of the fibrous pericardium?
Parietal
Which layers of the pericardium are innervated by pain fibres?
Fibrous pericardium and parietal serous pericardium
What is the role of the left and right auricles?
To increase the capacity of the atrium and increase the volume of the heart
Which tubular structure lies directly behind the left atrium?
Oesophagus
Which chamber forms the apex of the heart?
Left ventricle
Which chamber forms the base of the heart?
Left atrium
What is the function of the foramen ovale?
To allow blood to enter the left atrium from the right atrium bypassing the lungs
What is the function of the moderator band?
To act as a primary conducting pathway into the free wall originating from the right bundle branch
How many times thicker is the left ventricular wall than the right?
Three times
How many papillary muscles are found in the right ventricle?
Three
Which valve guards entry from the left atrium to the left ventricle?
Mitral valve
How many papillary muscles are found in the left ventricle?
Two
What is the function of the papillary muscles?
To contract and prevent the cusps of the valves from turning inside out
What is the function of the chordae tendineae?
To attach the cusps of the valve to the papillary muscles
From which part of the aorta do the coronary arteries rise?
From the left and right sinuses of the ascending aorta
Which pair of coronary arteries anastomose in the coronary sulcus?
RCA and Circumflex
Which pair of coronary arteries anastomose in the interventricular sulcus?
Anterior and posterior descending
Which cardiac vein runs alongside the anterior interventricular artery?
Great cardiac vein
Which cardiac vein runs alongside the posterior interventricular artery?
Middle cardiac vein
Which cardiac vein runs alongside the marginal artery?
Small cardiac vein
What lies alongside the circumflex artery?
Coronary sinus
Which veins drain directly into the right atrium?
Cardiac veins
Where is the cardiac plexus located?
At the bifurcation of the trachea
Which nerves pass through the cardiac plexus?
Vagus nerve and the spinal segments of T1-4
Where is the sinu-atrial node located?
Near the opening of the SVC in the right atrium
Where is the atrioventricular node located?
The inferior part of the interatrical septum
Where is the atrioventricular bundle (of His) located?
Either side of the interventricular septum
What type of artery are the aorta and pulmonary trunk?
Conducting and elastic
What type of artery are the radial and femoral arterie?
Distributing and muscular
