Cardiovascular Structures Flashcards
What are the two layers of the pericardium?
-fibrous layer
-serous layer
What are the two divisions of the serous pericardium?
-parietal
-visceral
How does the serous pericardium form as the heart grows?
Embryo heart cells push into the serous pericardium and and as they expand/grow they create a double layer wall known as the serous pericardium
What is the fibrous pericardium? WHat purpose does it serve?
Tough connective tissue that anchors the heart by connecting to the central tendon of the diaphragm and the sternum
What is the pericardiocophrenic ligament?
The tissue that anchors the fibrous pericardium to the central tendon of the diaphragm
Where does the phrenic nerve descend in relationship to the pericardium?
Phrenic nerve will descend between the fibrous pericardium and the mediastinal pleural walls
What does the serous pericardium do?
contains the heart
What does the parietal layer of the serous pericardium do?
Blends with the fibrous pericardium on the “outer layer”
What does the visceral layer of the serous pericardium do?
Blends with the epicardium (anchors and merges with the tissue of the heart)
What is the pericardial cavity?
Potential space between the parietal and visceral layers of the serous pericardium
*contains serous fluid which allows for the heart to move smoothly without friction
How does blood flow occur in chambers of the heart?
-Blood flows from the right atria to the right ventricle and heads out toward the lungs
-Blood then comes back to the left atria and moves into the left ventricle where it will be pushed through the aorta to supply the body
What are the landmarks of the right atriium?
-right auricle
-SVC/IVC openings
-opening to coronary sinus
-fossa ovalis
-tricuspid valve
What purpose do the SVC/IVC openings serve in the right atrium?
blood flows directly into the heart from these opening, no valve is present (just a gradient flow)
What purpose does the opening to the coronary sinus serve in the right atrium?
Venous return from the heart muscle itself
Coronary veins bring blood back to right atrium
Coronary arteries supply the heart itself (these veins/arteries merge into the coronary sinus)
What purpose does the fossa ovalis serve in the right atrium?
Represents the opening that was present between right and left atria in developing embryos (blood is received from mother, does not need to be oxygenated)
It is sealed off once heart is developed and is known as the fossa ovalis
What is the purpose of the tricuspid valve serve in the right atrium?
The AV (atrioventricular) valve that sits between the right atrium and the right ventricle (opens during blood flow from atrium to ventricle)
What is the right auricle of the right atrium?
Pouch/pocket that sits on the right atrium
What are the landmarks of the right ventricle?
-tricuspid valve
-papillary muscle/chordae tendineae
-pulmonary valve
What is the papillary muscle/chordae tendineae of the right ventricle?
Papillary muscle: continuation of cardiac muscle that anchors onto the chordae tendineae
-These keep the tricuspid valve from flopping back into the right atrium when closing
What is the pulmonary valve of the right ventricle?
The semi-lunar valve that sits between the pulmonary trunk and the right ventricle to allow unoxygenated blood to flow to the pulmonary system
What are the landmarks of the left atrium?
-left auricle
-valve of foramen ovale
-4 openings to pulmonary veins
-bicuspid (mitral) valve
What is the left auricle of the left atrium?
Small pouch/outpocket that sits on top of the left atrium
What purpose does the valve of the foramen ovale serve in the left atrium?
“other side” of fossa ovalis (now closed off opening that was present during embryo development)
What purpose do the 4 openings of pulmonary valves serve in the left atrium?
openings for the 2 right and 2 left pulmonary veins that are bringing oxygenated blood from pulmonary circulation back to the heart
What purpose does the bicuspid (mitral) valve serve in the left atrium?
AV valve that sits between the left atrium and the left ventricle (opens when blood flows)
What are the landmarks of the left ventricle of the heart?
-bicuspid (mitral) valve
-papillary muscle/chordae tendineae
-aortic valve
What purpose do the papillary muscle/chordae tendineae serve in the left ventricle of the heart?
Papillary muscle: continuation of cardiac muscle that anchors onto the chordae tendineae
-These keep the bicuspid valve from flopping back into the left atrium when closing
What purpose does the aortic valve serve in the left ventricle of the heart?
Left ventricle pushes blood (stroke volume) out into the aorta through the aortic valve
What is the fibrous skeleton of the heart?
4 fibrous rings that sit between the chambers of the heart and surround the orifices of the valves
What are the three functions of the fibrous skeleton?
-provide attachment for the cardiac valves
-provides attchments for the myocardium of the atria and ventricles (stabilizes/anchors them during contraction)
-Provides electrical insulation from electrical discharge between atria and ventricles (makes sure only one chamber contracts at a time)
Which valve is more anterior in the fibrous skeleton?
Pulmonary trunk
(aortic valve sits just behind it)
Which valve is on the left posterior part of the fibrous skeleton?
Bicuspid (mitral) valve
Which valve is on the right posterior part of the fibrous skeleton?
Tricuspid valve
What are the great vessels of the heart?
Superior and Inferior vena cava, aorta
What does the superior vena cava do?
returns blood back to the right atrium from areas superior of the diaphragm (except for the heart and lungs)
What does the inferior vena cava do?
returns blood back to the right atrium from areas inferior to the diaphragm
What does the aorta do?
sends blood to the body from the left ventricle
branches include: brachiocephalic trunk, left common carotid, left subclavian artery
Where do coronary arteries originate?
in the base of the heart
What does aortic pressure create? How do coronary arteries compensate for this?
Aortic pressure from large amount of blood being pumped out of the heart will create “backflow”
The backflow pushes on the aorta semilunar valve causing it to slam shut
The backflow then enters the coronary arteries as an escape route and supplies the cardiac wall of the heart with blood
**happens during early diastole/relaxation
What are the three branches of the RIGHT coronary artery? What do they supply?
-nodal branches: supply SA/AV nodes
-marginal branch: supplies right ventricle
-posterior interventricular artery (right posterior descending): supplies right ventricle *divides R/L ventricles
**RCA wraps around top of right ventricle to the back of the heart kind of in a straight line from the right side
What are the three branches of the LEFT coronary artery? What do they supply?
-anterior interventricular artery (left anterior descending): supplies septum and left ventricle
-circumflex artery: supplies left atrium and ventricle
-marginal branch: supplies left ventricle
**LCA splits a lot and wraps around the heart from the left side
Which coronary artery is known as the widow maker?
Left anterior descending, most prone to plaque buildup
What is the coronary sinus?
The “final pathway” of veinous return
-most cardiac veins drain into the coronary sinus and blood
-coronary sinus will drain directly into the right atrium
What is the superior border of the heart?
“imaginary” line along the great vessels
What is the left border of the heart?
line that runs along the left ventricle
What is the right border of the heart?
line that runs along the right atrium
What is the inferior border of the heart?
line that runs along the right ventricle
What is the apex border of the heart?
the inferior/lateral part of the left ventricle
“tip” of the left ventricle
What is another term for the apex of the heart?
PMI- point of maximal impact
or “apical impulse”
*good spot to auscultate to find any issues with left ventricle
What represents the base heart?
Back of the left atrium (can be spotted by observing the 4 pulmonary vein openings)
