thorax and heart Flashcards
the thoracic cavity contains organs of which 4 systems?
respiratory, cardiovascular, digestive, lymphatic system
how is the thoracic cavity subdivided?
R and L pleural cavities (surround lungs), mediastinum (central compartment), and pericardial (surrounds heart)
what are the anterior and posterior boundaries of the thoracic cavity
thoracic cage - ribs, sternum, thoracic spine, muscles
what is the inferior boundary of the thoracic cavity
diaphragm
where is the heart located with regards to the thoracic cavity?
middle mediastinum within pericardial cavity
posterior to sternum
between lungs
superior to the diaphragm
which way does apex of the heart point?
anteriorly, inferiorly, and to the left
how is the flow of blood within the heart controled?
via valves
which two circuits drive blood?
pulmonary and systemic
describe pulmonary circulation
right aorta pumps deoxygenated blood from the heart to the lungs to become oxygenated - this blood then goes from the lungs to the left ventricle
describe systemic circulation
left ventricle pumps oxygenated blood to the rest of the body and deoxygenated blood returns to the right aorta
what is the pericardium
the pericardium is a layered fluid filled sac that surrounds the heart
what is the pericardium formed by
outside: outer fibrous pericardium
inside: inner serous pericardium
what is the fibrous pericardium
outer dense connective tissue layer that surrounds the heart and the roots of the great vessels. The base of the pericardium is fused with the central tendon of the diaphragm
what is the central tendon of the diaphragm?
aponeurosis/flattened tenidnous thickening of the diaphragm
what is the function of the fibrous pericardium
anchors heart in place, provides protection, and prevents over extension of the heart
what forms the serous pericardium?
two layers: parietal pericardium which is going to be fused with fibrous pericardium and visceral pericardium which is going to be adhered to the surface of the heart
what is the pericardial cavity/space?
this is the space between the parietal and the visceral pericardium (both of which are apart of the serous pericardium)
what does the pericardial space contain? why?
the pericardial space contains a small amount of pericardial fluid that acts as a lubricant reducing friction between the opposing surfaces of the heart and the pericardium as the heart beats
what is a potential space?
when adjacent structures ARE NORMALLY pressed together
what is the potential space in the pericardial cavity?
the space btw the fibrous pericardium and the serous pericardium
what forms the apex of the heart?
the ventricles
how can you orient yourself when looking at the heart?
the apex points left and inferiorly
The RIGHT atrium is below and slightly lateral to the aortic arch (can tell its the arch because it curves and has 3 vessels coming off)
where is the right coronary artery when looking at the heart anteriorly?
RIGHT SIDE, coming from behind the pulmonary trunk
what seperates the chambers of the heart?
septa
what separates the left and right ventricles?
the intraventricular septum
what does the atrioventricular groove seperate?
right aorta and right ventricle
what does the anterior interventricular groove seperate?
right and left ventricles anteriorly
what does the posterior inter ventricular groove separate
right and left ventricles posteriorly
how do you orient yourself to the front of the heart?
ANTERIOR VIEW: aorta should be positioned pointing posteriorly, the pulmonary trunk is also pointing posteriorly/to the left, the apex should be pointing to the left and down, the right side is bigger than the left side, the superior and inferior vena cava should be opposite side to the apex
how do you orient yourself to the posterior of the heart
- aorta is pointing towards you (slightly to the left)
- the pulmonary trunk should be crossing from the left towards the right
- the left atrium should have L+R sup/inf pulmonary veins going into it
what veins drain blood into the atria
R: SVC and IVC
L: Pulmonary veins
which arteries bring blodo out off the heart?
L: Aorta
R: pulmonary trunk and pulmonary arteries
what is coronary circulation
arteries and veins that supply the heart muscle itself
What makes up arterial supply?
right coronary artery, left coronary artery, left anterior descending artery, and the circumflex artrery
where is the right coronary artery?
ANTERIORLY: starts at aorta and then goes in the atrioventricular groove (the groove separating the Ratrium and Rventricle)
Posterir: comes around to the back staying in the right aterioventricular groove and then down
where is th left coronary artery
ANTERIORLY: starts at aorta and moves straight across to the apex side of the heart
where is the left anterior descending artery?
ANTERIORLY: comes off of left coronary artery, travels down anterior interventricular groove
where is the circumflex artery?
ANTERIORLY: comes off left coronary artery and moves posteiorly
POSTERIORLY: comes around the left side of the heart, and moves below left atrium
Where is the posterior descenfing artery?
Comes off of the right coronary artery and travels down the posterior interventricular groove
what makes up the venous drainage of the heart?
Great cardiac vein, small cardiac vein, middle cardiac vein , and coronary sinus
what role does the coronary sinus play in venous drainage
veins of coronary circulation empty into the coronary sinus and then drain into the right atrium
where is the great cardiac vein?
ANTERIORLY: runs though the anterior interventricular groove
where is the small cardiac vein?
ANTERIORLY: runs through atriventricular groove
POSTERIORLY: also runs through atrioventricular groove on the back
Where does the middle cardiac vein go?
POSTERIORLY: runs up the interventricular groove
where is the coronary sinus>
POSTERIOLY - btw the left atrium and ventricle
where does the coronary sinus drain into?
the right atrium
where is deoxygenated blood drained into?
the RIGHT atrium
what drains blood into the rigth atrium?
Superior and inferior vena cava
what does the inferior vena cava drain?
lower limbs, pelvic and aadominal viscera
what does the IVC divide into at the belly button ish
common iliac veins
what does the superior vena cava drain
thorax, head, neck, and upper limbs
what veins contribute to the SVC
(R internal jugular, R subclavian) = the R brachiocaphalic and (L internal jugular and L subclavian) = Left brachiocarphalic
what is the fossa ovalis?
the closed foramen oval found as a depression on the interatrial septum within the right atrium
what does the tricuspid valve seperate?
R atrium and R ventricle
What does the bicuspid valve seperate?
L atrium and L ventricle
what are anatomical features of the right atrium?
pectinate muscles
Fossa ovalis
what are the vessels of the rigth atrium?
SVC, IVC, and the coronary sinus (drains into here)
What is the valve of the rigth atrium?
tricuspid valve
what are the anatomical features of the rigth ventricle?
Papilary muscles - muscles extending from wall that anchor choardae tendinae
Chordae tendinae - extensions that attach to valve cusps and prevent prolapse of the valve during contraction of ventricle
Traneculae carnea -muscle on inner surface of right ventricle that prevents inversion of the tricuspid valve
what are the valves of the right ventricle?
tricuspid valve (btw the R aorta and R ventricle)
Pulmonary valve (btw the R ventricle and the pulmonary trunk)
what are the vessels of the right ventricle?
pulmonary trunk which drains into L and R pulmnary arteries
what are the anatomical features of the left atrium?
pectinate muscles
what are the valves of the left atrium?
biscuspid valve (connects L atrium to L ventricle)
What are the vessels of the left atrium?
Pulmonary veins
What are the anatomical features of the left ventricle
Papilary muscles - muscles extending from wall that anchor choardae tendinae
Chordae tendinae - extensions that attach to valve cusps and prevent prolapse of the valve during contraction of ventricle
Traneculae carnea -muscle on inner surface of right ventricle that prevents inversion of the bicuspid valve
what are the vessels of the left ventricle
Aorta
What are the valves of the left ventricle?
Bicuspid valve (btw L aorta and L ventricle) and Aortic valve (btw L ventricle and Aorta)
What are the branches that come off of the arch of the aorta
brachiocaphalic trunk, left common carotid artery, left subclavian artery
what does the braciocephalic artery become (in order)
Right commn artery branches off and it continues as the right subclavian artery
what does the descending aorta supply?
blood to the thorax, abdomen, and lower limbs
when does descending aorta end and what does it split into?
the descending aorta ends near the belly button and it splits into L and R common iliac arteries
which ventricle has thicker walls?
the left ventricle bc it has to pump blood further
how is heart innervated?
autonomically - sumpatheically by sympathetic track and parasympathetically by CN10 *vagus
how does the posterior thoracic wall get blood?
the aorta contiues as the descending (thoracic) aorta which gives off posterior intercostal arteries that supply the posterior thoracic wall
how does the anterior thoracic wall get blood?
R and L subclavian arteries give off the internal thoracic artery that gives off anterior intercostal arterues
how is the thoracic cavity drained?
anterior and posterior intercotal veins drian into
RIGHT: azygous vein
LEFT: hemiazygous (lower) and the accessory hemiazygous (higher) veins then this will drain into the azygous vein
how is the thoracic cavity intervated?
the ventral rami of the thoacic spinal nerves form intercostal nerves
Motor: innervate intercostal muscles
Sensory: innervate overlying skin
