3. The lateral mediastinum and exterior of the heart Flashcards
what 3 vessels should be seen on the lung root?
- bronchi
- pulmonary artery
- pulmonary veins
origin of the phrenic nerve
spinal cord segment C3,C4,C5
function of phrenic nerve
motor innervation to the diaphragm for contraction
where does the L. phrenic nerve recieve sensory innervation from? (2)
- pericardium
- parietal pleura
name of foetal remnant in heart
ligamentum arteriosum
function of ligamentum arteriosum
allowed a shunt of blood to travel from the pulmonary trunk to the aorta without going to the lungs as they werent functioning
previous name of ligamentum arteriosum
ductus arteriosum
origin of vagus nerve
medulla oblongata
what type of nerve is the vagus nerve
cranial nerve
what type of nervous innervation does the vagus nerve give?
parasympathetic
where does the L.vagus nerve supply?
thoracic viscera
what 3 plexuses does the L.vagus nerve branch into ?
- cardiac plexus
- pulmonary plexus
- esophageal plexus
where does the L.vagus nerve branch?
at the lung root
what nerve does the L.vagus nerve branch into?
L. recurrent laryngeal nerve
what structure does the L. recurrent laryngeal nerve wrap around?
ligamentum arteriosum
what does the recurrent laryngeal nerves supply?
the muscles of the larynx
between what structures is the ligamentum arteriosum?
heart and arch of aorta
which nerve is more anterior; vagus or phrenic?
phrenic
where on the aorta does the phrenic nerve pass?
anterior to arch of aorta
which nerve runs on the lateral surface of the pericardium?
phrenic nerve
which nerve does the R. recurrent laryngeal nerve branch from?
the R. vagus nerve
where does the azygos vein drain into?
superior vena cava
what vein does the thoracic wall blood drain into?
azygos vein
which specific veins drain into the azygos vein?
intercostal veins
role of sup. vena cava
drains blood from the head, neck and upper limbs
which side of the heart is the superior vena cava on?
right side
2 branches of the sup. vena cava
right and left brachiocephalic veins
what do each of the brachiocephalic veins branch into (L+R)?
right and left;
- subclavian vein
- internal jugular vein
what nerve is attached to the trachea?
R. vagus nerve
which nerve runs down the sup. vena cava?
R. phrenic nerve
where is the sympathetic chain?
thoracic wall
what do the sympathetic nerves join to?
plexuses of the parasympathethic nerves
what is the sympathetic chain made up of?
ganglia
2 layers of pericardium
- serous
2. outer fibrous layer
2 layers of serous pericardium
- visceral
2. parietal
function of fluid in pericardial cavity
allows heart to beat smoothly
what 3 chambers of the heart can be seen anteriorly
LV. RA, RV
what chambers are visible on the posterior side of heart
all chambers
which side of the heart are the pulmonary veins visible
posterior
where is the right atrium in relation to the aorta
to the left
where can both the R + L coronary arteries be found
behind the appropraite auricles
another name for coronary sulcus
atrioventricular groove
where does the right coronary artery run
through the atrioventricular groove
between which chambers of the heart does the R. coronary artery run?
R atrium and R ventricle
branch of the R. coronary artery on the anterior side of heart
right marginal artery
branch of the R. coronary artery on the posterior side of heart
posterior interventricular artery
between which chambers of the heart does the posterior interventricular artery run
right and left ventricles - posterior side of heart
where does the posterior interventricular artery end?
left atrium
which blood vessel is close to the L. coronary artery?
pulmonary artery/trunk
which is shorter, the left or right coronary arteries?
left
2 branches of the L. coronary artery?
- circumflex artery
2. anterior interventricular artery
what does the circumflex artery branch into
left marginal artery
where is the coronary sinus on the heart?
posterior side - atrioventricular groove
role of coronary sinus?
recieves venous blood from heart - transports to right atrium
differentiation of superior and inferior mediastinum
the sternal angle of the sternum
3 subdivisions of the inferior mediastinum
- anterior
- posterior
- middle
what is the tracheal carina and where does it occur?
birfurcation of the trachea at the sternal angle (4th thoracic vertebra
function of thoracic duct
drains lymph from the body
why could an enlarged left sided supraclavicular lymph node a sign of?
lymphoma, thoracic cancer
what do the vagus nerves supply?
heart, lungs and digestive tract
what nervous fibres does the phrenic nerve carry?
autonomic and somatic
what nervous fibres does the vagus nerve carry?
autonomic
why might an intrathoracic tumour lead to loss of voice?
the recurrent largyngeal nerve puts pressure on the vocal cords
is the pulmonary plexus sympathetic or parasympathetic?
both
Effect of sympathetic stimulation on bronchi
bronchodilation
why should asthma patients never be given beta blockers?
beta blockers induce bronchoconstriction
Name of nerves which emerge from the sympathetic chain (medial)
splanchnic nerves
what is pericardial effusion?
passage of fluid from pericardial capillaries to the pericardial cavity
what is cardiac tamponade?
heart compression caused by build up of fluid in the pericardium
consequence if cardiac tamponade is not treated
circulation fails
which heart chamber contains the pulmonary veins?
left atrium
how many valves are in the heart?
4
Name of 2 atrioventricular valvues
tricuspid and mitral
which AV valve is on the right
tricuspid
2 semilunar values
- pulmonary valve
2. aortic valve
where is the pulmonary valve?
right ventricle and pulmonary artery
where is the aortic valve?
left ventricle and aorta
heart muscle
myocardium
where do the coronary arteries arise from?
aortic sinus
which coronary artery gives the greater supply to sinoatrial and AV nodes?
right coronary artery
name for smaller branches of coronary arteries
functional end arteries
what is a functional end artery?
has ineffected anastamoses
what is angina pectoris?
tightness of chest
what is a coronary thrombosis?
blockage of blood flow to the heart due to a blood clot in the coronary artery
what do all coronary veins drain into?
coronary sinus
where does the coronary sinus open into?
right atrium
affect of sympathetic stimulation on the heart
increase HR
affect of parasympathetic stimulation on the heart
decrease HR
where does pain from angina pectoris usually arise?
right
where is pain usually reffered in angina pectoris?
left arm and chest
why is pain referred to the left in angina?
pain radiates due to thoracic cord segments