Lecture 19: Middle Mediastinum Flashcards
Contents of the middle mediastinum
pericardium (the envelops phrenic nerves, heart, root of aorta, distal segment of the superior vena cava, pulmonary veins, inferior vena cava, pulmonary trunk, right pulmonary arteries, and right and left main stem bronchi)
What are the components of pericardium
Visceral and partietal pericardium create the pericardial cavity contains serous fluid- derived from intraembryonic coelomic space
Pericarditis
inflammation of the pericardial sac- can result in fluid accumulation in pericardial cavity which impedes the motion of the heart. Procedure to remove fluid is pericardiocentesis
Cardiac tamponade
The accumulation of fluid in the pericardial cavity that impedes the motion of the heart caused by inflammation of the pericardial sac
What are the two pericardial sinuses
oblique and tranverse
Transverse sinus
connects the right and left sides of the cavity, and separates the outflow tracts (aorta and pulmonary trunk) from the inflow tract (superior vena cava)
Oblique sinus
Inverted U-shaped on the dorsal to the left atrium between the pulmonary veins and superior vena cava
Clinical significance of these sinuses?
??
Are the right and left sides of the heart on the left and right sides of the thorax
no
What is the orientation of the heart after rotation during development
right ventricle is anterior and positioned to the left along with the left ventricle
What region of the heart comprises the base?
the posterior aspect
What region comprises the apex of the heart
left ventricle (the inferiolateral tip)
Where is the apex of the heart normally positioned?
5th intercostal space
Coronary sulcus
encircles the heart and discerns between the atrium and ventricles
Interventricular sulci
separates the two ventricles (one on the anterior and posterior)
Anterior surface of the heart
mainly right ventricle with a little right atrium
Posterior surface of heart
Left atrium with smaller portions of the left ventrical and right atrium
Diaphragmatic surface of hear
mostly right ventricle with a little contribution by the left ventricle
Superior boarder of heart
roots of aorta, pulmonary a., and superior vena cava
Where are the strongest heart sounds and why
left to the sternum because the heart is usually slightly left of the midline
Dextrocardia
when the heart is slightly right to the midline instead of left and results in the strongest heart sounds being to the right of the sternum
How does some endocardial tissues receive nourishment
via direct diffusion of oxygen and nutrients from blood within the cardiac chambers
Where do the coronary arteries and veins travel
beneath the epicardium (visceral peritoneum embedded in fat
What aortic sinus is the right coronary artery originated in?
right aortic sinus (of Valsalva)
What does the right coronary a. supply
Right atrium, right ventricle, and SA node
What are two important branches given off by the right coronary a.
nodal a. (posterior to right auricle) and right marginal a. (descending right cardiac border)
What does the left coronary a. supply
much of the left ventricle, small part of right ventricle, ventricular septum, and part of the left atrium
Where does the left coronary a course
arises from aorta and passes posterior to pulmonary trunk
Where does the left coronary a. branch
coronary sinus
What are the two branches of the left coronary a.
left anterioventricular branch and circumflex blanch
What gives rise to the left marginal a.
the circumflex artery
Where does the circumflex a. travel
in the coronary sulcus
What is the inter ventricular septum primarily supplied by?
branches of the left coronary a.
What does the nodal branch supply
right atrium and SA node (sin-atrial node)
What does the right marginal a. supply?
Anterior wall of the right ventricle
What does the posterior inter ventricular a. supply?
Posterior wall of the right ventricle and the posterior part of the inter ventricular septum
What does the anterior inter ventricular a supply?
anterior left ventricle, most of the anterior inter ventricular septum, apex