Thorax 3 Flashcards
What is the pericardium?
Fibroserous sac that
encloses the heart and
roots of great vessels
What are the 2 types of pericardium?
-Fibrous pericardium
-Serous pericardium
What are the 2 layers of the serous pericardium?
-Parietal layer
-Visceral layer
What is the shape of the fibrous pericardium?
Cone-shaped
What does the fibrous pericardium surround?
Surrounds the heart and roots of great vessels
What is the base of the fibrous pericardium attached to?
Its base is attached to middle part
of diaphragm’s central tendon and to
part of the left muscular dome
What is the apex of the fibrous pericardium continuous with?
Its apex is continuous with the
adventitia of the great vessels
How is the fibrous pericardium attached to sternum’s posterior surface?
Attached to sternum’s posterior
surface via sternopericardial
ligaments
What ligament attaches the fibrous pericardium to the xiphoid process?
Xipho-pericardial ligament
Where does the parietal layer of the pericardium lie?
Lies against the
internal surface of
the fibrous
pericardium
Where does the visceral later of the pericardium lie?
Lies against the
external surface of the
heart
What is the pericardial cavity?
Space between
parietal and visceral
layers
What fluid does the pericardial cavity contain
Contains minimal serous fluid
What layers make up the heart wall?
-Visceral serous
-Myocardium
-Endocardium
What is the course of the phrenic nerve within the thorax?
The phrenic nerve descends
anterior to the pulmonary
hilum between the fibrous
pericardium and mediastinal
pleura, accompanied by the
pericardiacophrenic vessels
What does fibrous pericardium and parietal serous pericardium receive sensory innervation from?
Fibrous pericardium &
parietal serous
pericardium receive
sensory innervation from
the phrenic nerve
What can irritation of fibrous pericardium lead to?
referred pain to dermatomes of
phrenic nerve’s roots
How many surfaces does the heart have and what are they?
The heart has 4 surfaces:
* Sternocostal surface
(anteriorly)
* Right pulmonary surface
-Faces the right lung
* Left pulmonary surface
-Faces the left lung
* Diaphragmatic surface
(inferiorly)
Where is the base of the heart located?
Directed posteriorly
Where is the apex of the heart positioned?
The apex of the heart is positioned
deep to the left 5th intercostal space
What does the coronary sulcus seperate?
Separates the atria from the ventricles
What does the right atrium form?
Forms the entire right border of the
heart
What nodes does the right atrium contain?
- Contains the SA node
- Contains the AV node
What does the right atrium open into and via what valve?
Opens in the right ventricle via the
right atrioventricular valve (tricuspid
valve)
What 3 veins does the right atrium receive blood from?
- Superior vena cava (SVC)
- Inferior vena cava (IVC)
- Coronary sinus
Where does the right atrium project from?
Projects anteriorly from the right atrium’s superior corner
What are pectinate muscles?
Irregular horizontal muscle ridges
What are crista terminalis?
C-shaped ridge
What is the crista terminalis important in locating?
Important landmark
in locating the sites
where veins enter the
right atrium
Where is the opening of the superior vena cava located in relation to the crista terminalis?
Opening of SVC is
posterior to crista
terminalis’ superior
bend
Where is the opening of IVC located in relation to crista terminalis?
Opening of IVC is
posterior to crista
terminalis’ inferior
bend
Where is the opening of the coronary sinus located in relation to the crista terminalis?
Anterior to the
inferior end of crista
terminalis
What is the fossa ovaus?
Depression in interatrial septum
What spot does the fossa ovaus mark?
Marks the spot where
foramen ovale existed
What is the most anterior surface of the heart?
Right ventricle
What ate trabeculae carnae?
Irregular muscular ridges
on the walls of the
ventricle
How do chordae tendineae project?
Project superiorly from
papillary muscles to tricuspid
valve’s cusps
What are papillary muscles?
Trabeculae carnae with only
one end attached to the
ventricular surface
What do papillary muscles serve as?
Serve as a point of
attachment for the chordae
tendinaeq
What are the 3 groups of papillary muscles in the right ventricle?
-Anterior
-Posterior
-Septal
What are papillary muscles named relative to?
Named relative to their point
of origin on the ventricular
surface
Where is the right atrioventricular valve located?
Located at junction between
right atrium and ventricle
How many cusps does the right atrioventricular valve have?
3 cusps
How many cusps does the pulmonary valve have?
Has 3 semilunar cusps
What forms almost entirely posterior surface of the heart?
Left atrium
What does the left atrium receive and from where?
Receives oxygenated blood
from the 4 pulmonary veins
What shape is the left auricile?
Triangular shaped
What lines the left auricle?
Pectinate muscles line the left auricle
only
What does the left atrium open into the left ventricle via?
Via the bicuspid valve
What does the left ventricle form?
Forms heart’s apex
What does the left ventricle dominate?
Dominates heart’s inferior surface
What does the left ventricle dominate?
Dominates heart’s inferior surface
What does the left ventricle contribute to?
Contributes to anterior and left
pulmonary surfaces
Where does the left ventricle lie?
Lies anterior to left atrium
What are the 2 groups of papillary muscles in the left ventricle?
-Anterior
-Posterior
How many cusps does the bicuspid valve have?
2 cusps
What does the aortic valve facilitate?
Facilitates the passage of blood
from left ventricle to ascending
aorta
Where do you auscultate for the tricuspid valves?
Left of the lower part of sternum
near 5th intercostal space
Where do you auscultate for the bicuspid valves?
Over heart’s apex in the left
fifth intercostal space at the
midclavicular line.
Where do you auscultate for the pulmonary valve?
Medial end of left
2nd intercostal
space
Where do you ascultate for the aortic valve?
Medial end of
right 2nd intercostal
space
What is the cardiac silhouette?
Outline of the heart as
seen on frontal and lateral
chest radiographs
What can the cardiac silhouette be divided into?
-Right and left borders
What is the right border of the cardiac silhouette formed by?
The right border is formed by
the right atrium
* Superior vena cava
entering superiorly and the
inferior vena cava often
seen at its lower margin
What is the left border of the cardiac silhouette formed by?
The left border is formed by
the left ventricle and left
auricle
* Pulmonary artery
What are the 5 great vessels of the heart?
- Superior vena cava
- Inferior vena cava
- Pulmonary Trunk
- Ascending Aorta
- Arch of Aorta
What is the superior vena cava formed by the union of?
Formed by the union of the
right & left brachiocephalic
veins
Where does the superior vena cava receive its systemic blood from?
Receives systemic blood from
all body regions superior to the
diaphragm excluding the heart
wall
What does the inferior half of the superior vena cava lie within?
Its inferior half lies within the
fibrous pericardium
What is the inferior vena cava formed by the union of?
Formed by the union of the
right & left common iliac veins
at L5
Where does the inferior vena cava receive its blood flow from?
Returns blood to the heart
from all regions of the body
inferior to the diaphragm
At what vertebrae level does the inferior vena cava pass through the diaphragm?
Passes through the diaphragm
at the vertebral level of T8
Where does the superior half of the inferior vena cava lie?
Its superior half lies within the
fibrous pericardium
Where does the pulmonary trunk lie?
Lies anterior and to the
left of the ascending
aorta
What does the pulmonary trunk divide into?
Divides into right and left pulmonary arteries
Where does the right pulmonary artery lie?
Right pulmonary
artery lies posterior to
ascending aorta &
superior vena cava
Where does the left pulmonary artery lie?
Left pulmonary artery
lies inferior to arch of aorta
Where does the ascending aorta arise from and how many cm does it ascend?
Arises from the left
ventricle and ascends
~5cm
Where does the ascending aorta begin?
Begins posterior to the
pulmonary trunk
What are the 3 branches the aortic arch gives off?
-Brachiocephalic trunk
-Left common carotid artery
-Left subclavian artery
What does the brachiocephalic trunk further branch off to?
-Right subclavian artery
-Right common carotid
What do the coronary arteries arise from?
Arise from the aortic sinuses in
the ascending aorta
Where does the right coronary artery originate from?
Originates from right aortic sinus of
ascending aorta
What does the right coronary artery run in?
Runs in the coronary sulcus
How does the right coronary artery run at the inferior margin of the heart?
At the inferior margin of the heart, it
turns posteriorly and continues onto the
diaphragmatic and base of of the heart
What does the right coronary artery supply?
-Right atrium
-Right ventricle
-SA and AV nodes
-Interatrial septum
-Parts of left atrium and ventricle
-Posteroinferior 1/3rd of interventricular septum
What are the branches of the right coronary artery?
-Atrial branch
-Right marginal branch
-Posterior interventricular branch
-
What does the atrial branch of the right coronary artery branch into and what does it supply?
Atrial branch branches to SA nodal
branch
*Supplies SA node
What does the right marginal branch supply?
Supplies right ventricle
What does the posterior interventricular branch supply?
Supplies posteroinferior 1/3rd
of interventricular septum
What are the branches of the left coronary artery?
-Anterior interventricular artery
-Left marginal artery
What is the anterior interventricular artery also known as?
Left anterior descending(LAD)
How does LAD run?
Runs in the anterior
interventricular sulcus
What does LAD supply?
Supplies anterior walls of
both ventricles &
interventricular septum
What is the left marginal artery also known as?
Left circumflex artery
What does the left circumflex artery supply?
Supplies left atrium and posterior part of left ventricle
What are the cardiac veins?
- Coronary sinus
- Great cardiac vein
- Middle cardiac vein
- Small cardiac vein
- Anterior cardiac veins
- Posterior cardiac vein
What does the anterior cardiac vein drain into
Directly into the right atrium
What does the coronary sinus receive blood from?
- Great cardiac vein
- Middle cardiac vein
- Small cardiac vein
- Posterior cardiac veins
What cardiac veins run in the anterior interventricular sulcus?
-Anteriorinterventricular artery
-Great cardiac vein
What cardiac veins run in the posterior interventricular sulcus?
Posterior ventricular artery
& Middle cardiac vein
running in the posterior
interventricular sulcus
What determines coronary dominance?
- The coronary artery giving rise to
the posterior interventricular artery
