Heart and Mediastinum Flashcards
what forms the right and left boarders of the cardiac shadow
right boarder- SVC, RA, IVC
left boarder- AA, LV, pulmonary trunk
what chamber of the heart is most anterior
right ventricle
what chamber is most posterior
left atrium
where is the apex of the heart on the chest surface
ICS 5, medial to midclavicular line
if a clot blocks the circumflex branch of the left coronary artery, what area of heart musculature will be ischemic
part of the left ventricle
what is in the mediastinum?
heart esophagus trachea great vessels thoracic duct
what are the divisions of the mediastinum
superior
anterior
posterior
middle
where is the superior mediastinum?
superior to the sternal angle line up to thoracic aperture
what is in the superior region of the mediastinum
brachioecphalic veins upper SVC aortic arch and branches thoracic duct esophagus trachea upper thymus vagus nerve recurrent laryngeal nerves phrenic nerve
where is the inferior region of mediastinum? what regions are in it?
inferior to the sternal angle
divided by the pericardium into anterior, posterior and middle regions
where is the anterior region of mediastinum?
anterior to pericardium
what is in the anterior region of mediastinum?
lower thymus
fat
lymph nodes
connective tissue
where is the posterior region of mediastinum?
posterior to pericardial sac
what is in the posterior region of mediastinum
esophagus thoracic aorta azygous hemiazygous thoracic duct vagus nerve sympathetic nerves
where is the middle region of mediastinum?
pericardial sac
what is in the pericardial sac?
pericardium heart roots of great vessels arch of azygous vein main bronchi phrenic nerves
what is the pericardium?
double walled sac containing the heart and great vessels
located around the middle region of the mediastinum
what are the two layers of pericardium
fibrous pericardium- outer tough layer
serous pericardium- inner smooth lining
what are the layers of the serous pericardium?
parietal serous- lines fibrous pericardium
visceral serous- covers the heart
visceral serous layer is the equivalent of the
epicardium
where is the pericardial cavity and what is in it
between the parietal and visceral serous layers
contains serous fluid
where are the parietal and visceral pericardium continuous
roots of great vessels
what are sternopericardial ligaments
connect the fibrous pericardium to the posterior sternum
what are the pericardiophrenic ligaments
connects fibrous pericardium to central tendon of diaphragm
what is the role of the fibrous pericardium
prevents heart from over filling
describe each layer of the heart wall
epicardium- visceral pericardium
myocardium- cardiac muscle
endocardium- endothelium and sub endothelium CT that covers valves
what is the blood supply of the parietal layer?
pericardiacophrenic artery
where does the pericardiacophrenic artery come from and go to?
branch of internal thoracic artery and runs with the phrenic nerve
what is the venous drainage of the parietal layer of pericardium?
pericardiaphrenic vein
what does the pericardiacophrenic vein drain into?
brachiocephalic or internal thoracic veins
what is the fibrous pericardium fused to and what effect does it have
fused to outer layer of great vessels, posterior surface of sternum, central tendon of diaphragm
influenced by the movements of the heart, great vessels, sternum, and diaphragm
what supplies the visceral layer of pericardium?
coronary artery and branches from descending aorta
what drains the visceral layer of pericardium
coronary vein and coronary sinus tributaries
what forms pericardial sinuses
intersection of visceral and parietal layers at the roots of great vessels
what are the two pericardial sinuses
transverse and oblique
where is the transverse pericardial sinus and how is it formed
anterior to SVC, posterior to aorta and pulmonary trunk
formed by the arterial and venous ends of the heart tube coming together
what is good about the transverse pericardial sinus?
place to tie ligatures and insert tubes during surgery
where is the oblique pericardial sinus and how is it formed?
between the pulmonary veins
formed by vein expansion, pushing a pericardial reflection out around them
do the pericardial sinuses touch
no
what is pericarditis
inflammation of pericardium due to infection or a systemic illness
what causes pericardial rub
friction between the layers of the pericardium due to inflammation
what is a pericardial effusion and what does it cause
fluid from pericardial capillaries getting into the pericardial cavity
causes cardiac tampanade- heart can’t fill because the fibrous pericardium doesn’t stretch
what is a pericardiocentesis
removing fluid from the pericardial space by inserting a needing into the bare area at ICS5
what is hemopericardium?
blood in the pericardial cavity
what causes hemopericardium?
stab wound
weak area of heart muscle
bleeding from cardiac operations
what are the components of the fibrous skeleton of the heart
4 fibrous rings (annuli fibrosa) around each valve
2 fibrous trigone- ring connections
3 membranous septums- interarterial, interventricular, atrioventricular
what is the function of the fibrous skeleton of the heart?
myocardium attachment
keeps valves open and prevents overextension
attachment for leaflets and valve cusps
electrical insulation
AV bundle goes through to get signal to the ventricles
what structures form the right boarder of the heart?
superior vena cava
right atrium
inferior vena cava
what structures form the left boarder of the heart
aortic arch
pulmonary trunk
left ventricle
what is the superior boarder of the heart
atria and auricles
what is the inferior boarder of the heart
IVC
RV
LV
what is the width of a normal heart
less than the width from the midsternal line to the lateral rib line
where does the heart sit relative to the midsternal line?
1/3 on right
2/3 on left
blood flow through the heart
- SVC and IVC empty into RA
- RA pumps through tricuspid valve to RV
- RV pumps through pulmonary valve to pulmonary trunk
- pulmonary veins return blood to LA
- LA pumps through mitral valve to LV
- LV pumps through aortic valve to aorta
where is the tricuspid valve and where can it be auscultated
posterior to sternum body at ICS 5 and 6
listen left side of sternum at ICS 4 or 5
what are the cusps of the tricuspid valve
anterior
posterior
septal
what is the role of the cordae tendinae and papillary muscles
contraction of the papillary muscles during RV contraction holds the valve closed to prevent back flow
where is the pulmonary valve and where can it be listened to
left costal cartilage 3
listen at upper left of sternum at ICS 2
what are the cusps of the pulmonary valve
semilunar valve- anteiror, left, right
where do the valves sit when open
against pulmonary artery
how does the pulmonary valve prevent backflow
when blood comes back, the valves close and form pockets preventing back flow
what is the pulmonary sinus
little pocket superior to pulmonary valve that holds blood to prevent the cusps of the pulmonary valve from sticking to the wall
where is the mitral valve and where is it listened to
posterior to sternum at ICS 3/4
listend to left of sternum at ICS 5
what are the cusps of the mitral valve
anteiror and posterior
where is the aortic valve and where can it be listened to
posterior sternum at ICS3
right of sternum at ICS2
what are the cusps of the aortic valve
semilunar valve
anterior- right and left
posterior- in the back
what is the lunule
midpoint of the cusps of the aortic valve that come together in the center when the valve is closed
what is the aortic sinus
dilation in the aorta superior to the valve
what comes immediately off of of the aorta
coronary arteries
what is apex beat
max point of pulsation against the anterior thoracic wall
where are the auscultation locations relative to the heart valves?
downstream of the valve location
valve stenosis
stiff valve doesn’t open all the way resulting in hypertrophy of the chamber before it
valve incompetence (regurgitation)
incomplete valve closure resulting in blood moving backward into the previous chamber during contraction
what is the most commonly diseased valve?
mitral
what are auricles for?
located on the superior portion of atria, used to increase capacity if ncessary
what is the sinus venarum?
smooth posterior right atria chamber wall
what is the pectinate muscle?
rough musculature anterior right atria wall
what is the sulcus terminals?
external groove separating separating anterior and posterior atria wall
what is the crista terminales
internal vertical ridge separating smooth and rough atrial wall
what vessels empty into the RA?
IVC
SVC
coronary sinus
what separates the right and left atrium?
internal septum
what and where is the fossa ovalis
depression left from the closure of the foramen oval during development (hole between the atria)
located in the internal septum
what are the 5 differences between the left and right atria?
smaller thicker walls 4 pulmonary veins empty into it mostly smooth walls valve is bicuspid
what is the cornosus arteriosus?
superior, leads to pulmonary trunk in the right ventricle
what is the trabecular carneae?
irregular muscular ridges in the right ventricle
what chambers are papillary muscles and chord tendinae in?
ventricles
what separates the ventricles
interventricular septum
what is the septomarginal trabeculae
muscular bundle stretching from the inter ventricular septum to the anterior papillary muscle and carries the righ bundle branch of the av bundle
moderator band
septomarginal trabeculae
cornosus arteriosus
infundibulum
how is the left ventricular different from the right ventricle?
thicker walls
bicuspid valve- 2 papillary muscles
aortic valve
what are the muscular ridges called in the right atria vs ventricles
atria- pectinate muscle
ventricle- trabeculae carneae
what is the aortic vestibule
superoanterior area of LV leading to aortic surface
which ventricle has more trabecular carneae?
left
what supplies blood to the myocardium and epicardium?
coronary arteries
where do the left and right coronary arteries come from?
aorta- first branches off from aortic sinus
where does the right coronary artery run
in the coronary sulcus (atrioventricular groove)
what are the branches of the right coronary artery and where do they go
sianonodal branch- SA node
right marginal branch- right heart boarder, runs toward apex
posterior inter ventricular branch- runs in posterior inter ventricular groove toward apex, supplies ventricles
what forms the anastamosis of the heart and where
RCA with the circumflex and inter ventricular branches of the LCA
where does the left coronary artery run
off of left aortic sinus
goes between the left auricle and pulmonary trunk to run in coronary groove
what are the branches of the LCA and where do they go
left circumflex branch- around left boarder to posterior side gives off left marginal branch that supplies LV
anterior inter ventricular branch- goes along inter ventricular septum and supplies both ventricles and the septum
what do the cardiac veins drain into?
coronary sinus or directly into right atrium
where is the coronary sinus?
runs left to right in the posterior coronary groove
receives blood from great, middle, and small cardiac veins
where is the great cardiac vein
from apex and comes up with the anterior inter ventricular artery from the LCA
wraps around the left heart
where is the middle cardiac vein
travels with posterior inter ventricular artery o f the RCA
where is the small cardiac vein
runs with right marginal artery of the RCA
where are the anterior cardiac veins and what do they drain into
begin at anterior right ventricle and empty into the right atrium directly
what is coronary artery disease
occlusion of coronary artery caused by atherosclerosis leading to inadequate oxygen to myocardium
myocardial infarction
myocardial necrosis and severe chest pain that does not go away
angina pectoralis
arterial constriction leading to oxygen deficiency and pain that is alleviated with rest (pain only during activity)
what vein is used for a coronary artery bypass graft?
great saphenous vein
what is coronary angioplasty
balloon catheter inserted and inflated to stretch open an occluded artery
path of cardiac conducting system
SA node-> AV node-> bundle of his->right bundle branch-> left bundle branch -> purkinje fibers
what is the SA node
pacemaker located under the epicardium between the SVC and RA that generates impulses
what is the AV node
interventricular septum near the coronary sinus that gets a signal from the SA node after a delay and sends the signal to the ventricles via the bundle of His
what is the bundle of His
bridge between atrial and ventricular myocardium that passes through the fibrous skeleton along the inter ventricular septum
what are the left and right bundles
split of the bundle of his on either side of the inter ventricular septum that lead to purkinje fibers
what are purkinje fibers
take the impulse into the ventricular walls
where are the right purkinje fibers
IV septum muscle
anterior papillary muscle
right ventricular wall
where are the left purkinje fibers
IV septum
anterior and posterior papillary muscles
left ventricular wall
what can compress the esophagus
aortic arch
left main bronchus
where the esophagus goes through the diaphragm
where are the phrenic nerve and pericardiacophrenic vessels
anterior to the root of the lung between the mediastinal pleura and pericardium
where does the pleura transition from parietal to visceral?
root of the lung
what structures are on the right of the mediastinum
thymus right brachiocephalic vein superior vena cava trachea right vagus and phrenic nerves esophagus thoracic duct azygous thoracic splanchnic nerves
what structures are on the left side of mediastinum
thymus left brachocephalic arch of aorta left vagus and phrenic nerves thoracic duct esophagus thoracic aorta esophageal plexus thoracic splanchnic nerves
what are the great vessels
aorta
pulmonary trunk
superior/infereior vena cava
4 pulmonary veins
what is the ligamentum arteriosum
connects the aortic arch to the left pulmonary artery
where does the left vagus nerve pass over
crosses over the left side of the aortic arch and then passes behind the left pulmonary arter
where is the left recurrent laryngeal nerve
off of the vagus nerve, inferior to the aortic arch and posterior to the ligamentum arteriosum
which heart boarders are easily seen on a chest radiograph
right
inferior
left
where is the a lex of the heart
left ICS 5, 9cm from midline
what forms the base of the heart
left atrium and right atrium
where does the pericardium switch from serous parietal to serous visceral
root of great vessels
what is in the pericardial cavity
serous fluid
where is the right atrium
ICS3
where is the coronary sulcus
atrioventricular sulcus
separates the atria from ventricles
begins near aorta and descends on the right
vessels lie in it
where is the inter ventricular sulcus
on the left between the ventricles
anterior and posterior aspects
vessels lie in them
intersects the coronary sulcus at a right angle
what makes the sternocostal surface
right ventricle
what makes the diaphragmatic surface
left ventricle
what is the left pulmonary surface
left ventricle
where heart makes the cardiac impression on the left lung
what is the right pulmonary surface
right atrium
where it makes cardiac impression on right lung
what is the order of the great vessels right to left
superior vena cava
aorta
pulmonary trunk
where is the posterior inter ventricular sulcus
under inferior vena cava
where is the anterior interventricualr sulcus
under the left auricle
where are the vessels of the heart located
between the visceral pericardium and the muscular wall
which is more superficial cardiac veins or arteries
veins
where is the coronary sinus and what does it empty into
diaphragmatic surface (posterior, below the pulmonary veins
in the coronary sulcus and ends before the inferior vena cava
right atria
where is the great cardiac vein
superior to the coronary sinus, under the left pulmonary veins
what sulcus does the great cardiac vein run in
anterior interventricular sulcus
what sulcus does the middle cardiac vein run in
posterior interventricular sulcus
where is the middle cardiac vein
below the inferior aorta
empties into the coronary sinus
where is the small cardiac sinus
perpindicular to the middle cardiac vein, in line with the coronary sinus
where are the anterior cardiac veins
cross over the atriventricular sulcus between the right atrium and right ventricle
pass superficial to right coronary artery
what do the anterior cardiac veins drain
anterior wall of right ventricle and directly into right atrium
where is the right vagus nerve
between the right carotid artery and the right internal jugular vein
where is the right recurrent laryngeal nerve
branch of right vagus nerve
passes anteirorly to subclavian artery and then dives deep
where are the cusps of the aortic valve
right and left are anterior
posterior is in the back
where is the aortic sinus
behind each of the cusps of the aortic valve
where do the coronary arteries come off
left- left coronary sinus right near the left cusp of the aortic valve
right- right coronary sinus next to the right cusp of the aortic valve
where is the left coronary artery
between the left auricle and the pulmonary trunk in the coronary sulcus
what sulcus is the anterior inter ventricular branch in
anterior ventricular sulcus
what is the LAD artery
left anterior descending artery
anterior inter ventricular branch of the left coronary artery
what vein runs with the LAD
great cardiac vein
what does the circumflex branch of the left coronary run with
coronary sinus
what sulcus is the circumflex branch in
coronary sulcus on the left
where does the RCA originate
coronary sulcus between the right auricle and the ascending aorta
where does the anterior right atrial branch come from
near the beginning of the RCA
what does the anterior right atrial branch of the RCA give off
sinu-atrical nodal branch which goes to the SA node
what does the RCA run in
coronary sulcus on the right
where does the right marginal branch of the RCA come from
near the inferior boarder of the heart
what vein does the right marginal branch run with
small cardiac vein
when does the posterior inter ventricular branch start
when the RCA gets to the posterior inter ventricular sulcus
where and what forms the anastamosis of the heart
posterior inter ventricular and anterior inter ventricular arteries
in the inter ventricular sulcus
what vein runs with the posterior inter ventricular branch
middle cardiac vein
where are the pectinate muscles
anterior wall of the right atrium
where is the crista terminalis
vertical ridge of muscle connecting the pectinate muscles
where is the ostium of the coronary sinus
in the posterior right atria between the inferior vena cava and the AV valve opening
where is the interatrial septum
between the atria, where the fossa ovalis is
where is the sinus venarum
area of the right atrial wall between the openings of the vena cavae
where is the brachiocephalic trunk
right side, gives off subclavian and right carotid arteries
where is the brachiocephalic artery
none, only veins
the artery is the brachiocephalic trunk which is only on the right side
where are the brachiocephalic veins
lead into superior vena cava
where are the left common carotid and left subclavian arteries
come off of the aortic arch
where are the brachiocephalic veins
left and right sides, lead into the superior vena cava
where are the cusps of the tricuspid valve
anterior- in front
posterior- in back
septal- on left side
which papillary muscle in the right ventricle is the largest
anterior
where do the cordae tendinae attach in the right ventricle
adjacent sides of 2 cusps
where are trabecular carneae
right ventricle
where is the septomarginal trabecula
from the inter ventricular septum to base of anterior papillary muscle
moderator band
septomarginal trabecula
where are the cusps of the pulmonary valve
anterior- front
right and left- back
where are the pectinate muscles in the right atrium
auricle
where are the cusps of the mitral valve
anterior
posterior
where is the thymus
anterior in superior mediastinum
what is the relationship between the superior vena cava and the right lung root
superior vena cava passes anterior to the root of the right lung
where does the arch of the zaygos vein pass
superior to the root of the right lung
relationship between the phrenic nerves and brachiocephalic veins and the lung roots
phrenic nerves passes posteriorly to brachiocephalic veins and anterior to lung roots
what do the laryngeal nerves do
vocal cord innervation
relationship between trachea and esophagus
trachea is anterior
esophagus is posterior
what side of midline is esophagus
right
what side is the thoracic aorta to the midline
left
where is the thoracic duct
between the azygos vein and the thoracic aorta
posteiror to the esophagus
where is the sympathetic trunk
ribs 2-9
where are sympathetic ganglion
one for each thoracic vertebra level
where is the greater splanchnic nerve
gets fibers from 5-9 sympathetic ganglia
located on T5-9 between the sympathetic trunk and the esophagus
where is the lesser splanchnic nerve
between the sympathetic trunk and the greater splanchnic nerve starting at T10
