mediastinum Flashcards
Mediastinum is the _____ of thoracic cavity
Middle
Mediastinum boundaries
Thoracic inlet above
Diaphragm below
Sternum anteriorly
T vertebrae posteriorly
Lungs laterally
Mediastinum is subdivided into ___ mediastinum and ___mediastinum
Sup
Inf
Inferior mediastinum subdivided into three portions
Ant
Middle
Post
Sup Mediastinum is directly behind…
Manubrium
Structures in the superior mediastinum
Thymus gland (T lymphocytes)
Great vessels: brachiocephalic vein, arch of the aorta call mom pulmonary trunk
Trachea (primary bronchi bifurcation)
N: vagus and phrenic
Esophagus
Vagus n carries
Sensory afferents from the heart/lung/gut and parasympathetic efferents to the larynx and heart/lung/gut
L recurrent laryngeal n hooks around ____, R recurrent laryngeal n hooks around ____
Aorta
R subclavian artery
(Innervate internal larynx musc: speech & swallowing)
Ant mediastinum betw
Body of sternum and pericardium
Middle mediastinum is where ___ sits
Heart
What’s sack surrounds the heart allowing it to beat freely without friction and is attached to the diaphragm and great vessels?
Pericardium
Fibrous pericardium is a tough fibrous outer layer covering the heart and is attached to the ____
Diaphragm
Serous pericardium is composed of two inner layers
Parietal and visceral pericardium (epicardium)
Pericardial layers from superficial to deep
Fibrous pericardium
Parietal pericardium
Pericardial cavity
Visceral pericardium
Heart is mostly the ___ pointing toward left hip in about the fifth intercostal space
LV
Base of the heart is the ___ that are positioned behind the ventricles
Atria
Grooves on heart surface that split heart into chambers
Sulci
Sulci:
Coronary (atrioventricular sulcus): sep atria fr ventr
Ant interventricular sulcus: sep RV & LV ant
Post interventricular sulcus: sep RV & LV post
Heart vasculature
RCA (coronary artery)
LCA
RCA gives odd
R marginal artery which descends inf to feed RV
Venous drainage for R marginal artery
Sm cardiac vein (empty into coronary sinus—> RA)
RCA becomes
Post interventricular artery (post descending) vascularize post heart
Venous drainage for post interventricular artery
Middle cardiac vein
RCA usually vascularized
All RV, 30% LV
60% SA node, 80% AV node
LCA splits into
Ant interventricular artery (ant descending)
Circumflex artery
Ant interventricular artery (ant descending)feeds…
Venous drainage?
LV & interventricular septum
Gr cardiac vein
Circumflex artery gives off
L marginal artery
Post L ventricular artery
Coronary sinus
LCA feeds
70% LV, 40% SA, 20% AV node
___ sealed opening fr fetal bypass called the foramen ovale
Fossa ovalis
Pectinate musc
Muscular ridges anterior wall of the RA
Sinoatrial node (pacemaker) inf and lat to ___ opening
Sup vena cava
Atrioventricular node electrical conduction
Bundle of His
R&L bundle branches
Purkinje fibers
RV&LV
R valve
Tricuspid (R atrioventricular valve)
Tricuspid valve is attached to ___ to the papillary muscles
Cordae tendonae
___ is the smooth outlet track from the RV into the pulmonary trunk via pulmonary valve R semilunar valve
Infindibulum (conus arteriosus)
Semilunar valves (pulmonary valve) have 3 cusps with no ___ attached
Cordae tendonae or papillary musc
L valve
Bicuspid (L atrioventricular, mitral valve)
Nordic sinuses are the areas behind the aortic valve cusps we’re blood flows into the R and L coronary arteries during
Diastole
