Lab 7: Heart and Mediastinum Flashcards
Describe boundaries of mid mediastinum
Sup = sternal angle
Inf = diaphragm
Ant and post = fibrous pericardium
Name roots of great vessels visible in mid mediastinum
Aorta
Pulmonary trunk, pulmonary arteries =x2 and pulmonary veins = x4
Ivc and svc
What is ligamentum arteriosum
Ductus arteriosus closes = remnant
Shunt between pulmonary trunk and aorta - bypasses lungs
Name neurovasculature outside pericardium
Phrenic
Pericardiophrenic vessels
Describe phrenic
In front of hilum and vagus - posterior to hilum
Cardiac plexus
Describe pericardiophrenic vessels
Arteries and veins
Run with phrenic nerves
What else can we see in mid mediastinum
Coronary circulation
Heart and pericardial coverings
Primary bronchi = left and right
Name the layers of the pericardium and their function generally
Serous membrane, pericardial cavity = potential space
Fibrous pericardium
Parietal serous pericardium
Visceral pericardium
Describe fibrous pericardium
Attaches to diaphragm and sternum
Encompasses all, anchored to root of gre vessels and at diaphragm
Pericardial fat
Describe parietal serous pericardium
Against fibrous
Describe visceral serous pericardium
Against heart
Epicardial fat
Describe coronary arteries
First branch aorta
Blood to heart
Describe coronary sinus
Means you are posterior in av sulcus
Drains into right atrium along with svc and ivc
Opening close to ivc
Name and describe branches of right coronary artery
Sinoatrial nodal branch = runs between svc and aorta towards posterior aspect, under - around auricle of right atrium
Right marginal artery = apex, towards side
Posterior interventricular artery = middle back, in some people = comes from left coronary
Name and describe branches of left coronary artery
Anterior interventricular artery = big, down middle
Circumflex branch = around back and gives =
Left marginal artery = comes down sides
Describe venous drainage of heart - mainly
Great cardiac vein = travels with anterior interventricular artery then with circumflex a
Middle cardiac vein = travels with posterior interventricular artery
Small cardiac veins = travels with right marginal artery
Where do great, middle and small cardiac veins drain
Into coronary sinus
Where do anterior cardiac veins drain
Right = drains into right atrium
Describe psns and sns for heart
Sns = increase hr, sympathetic chain
Psns = decrease hr, vagus branches
Describe filling of coronary arteries
Filled during diastole = ventricular relaxation
Aortic valve must be closed (semilunar)
Excess blood filled up valve
Describe right atrium and ventricle
Pulmonary circulation
Atrium = collect deoxygenated from body = svc, ivc, and coronary sinus (all but svc has valves)
Ventricle = deoxygenated from atrium and pump to pulmonary trunk and arteries (left and right)
Describe characteristics of right atrium
Svc and ivc openings into here
Opening for coronary sinus = near ivc
Fossa ovalis = circular indent, shunts = right to left atrium
Auricle
Pectinate muscle
Crista terminalis
Describe walls of right atrium
Smooth posterior wall
Ant and lateral = pectinate muscle, expand without stress on wall
What is crista terminalis of right atrium
Line, junction between pecitinate and smooth muscles
Describe right ventricle
Right av valve = tricuspid
Connects cusps to chordae tendinae and papillary muscles
Trabeculae carnae= wall texture
Pulmonary valve = lead to pulmonary trunk
Septomarginal = aka moderator band
Describe cups of right av valve - tricuspid
3 lobes like lung
Ant, post and septal cusps
What is fiction of papillary muscles
When shut during systole = Prevent backflow = holds cusps, prevent PROLAPSE
Describe aortic and pulmonary valve
Both have 3 cusps
Semi lunar for both
Describe left atrium and ventricle
Systemic circulation
Describe left atrium
Auricle
Openings for pulmonary veins x4
Reverse imprint of fossa ovalis
less pectinate muscle
Describe left ventricle
Left av valve = bicuspid/mitral valve = only 2 cusps
Chordae tendinae and papillary muscles = 2 sets
Trabeculae carnae
Aortic valve leading to ascending aorta
Ventricle = way thicker = to whole body
Describe borders of anterior mediastinum
Ant = sternum
Post = anterior surface pericardial sac
Sup= sternal angle
Inf= diaphragm
Lat= mediastinal surface of lungs
Describe contents of anterior mediastinum
Thymus Gland = lymphoid, T cells, degeneration in adults
Fat
Ct
Describe border of superior mediastinum
Ant = manubrium - sup vs inf = manubriosternal joint
Post = vertebrae and thoracic wall
Superior = rib 1/superior thoracic aperture
Inferior = thoracic plane - plane between sternal angle and vertebrae t4/5
Lat= mediastinal surface of lungs
Describe contents of superior mediastinum= arterial
Arterial = branches of arch of aorta: 1 brachiocephalic trunk (right subclavian and common carotid), 2 left common carotid, 3 left subclavian
Describe difference between right and left vagus nerves
Right = under right subclavian artery, outside mediastinum
Left =in superior mediastinum, under aortic arch
Describe posterior mediastinum borders
Ant= post surface of pericardial sac
Post = posterior thoracic wall
Superior = thoracic plane, plane between sternal angle and vertebrae t4/5
Inferior = diaphragm
Lat = mediastinal surface lungs
Describe contents of posterior mediastinum = arterial
Arterial = thoracic -descending aorta (posterior intercostal arteries)
Describe contents of superior mediastinum = venous
Venous = right and left brachiocephalic veins margining into svc, arch of azygous
Describe contents of superior mediastinum = nerves
Nerves = right and left vagus and their recurrent laryngeal branches, right and left phrenic nerves, sympathetic chain, cardiac plexus, pulmonary plexus
Describe contents of superior mediastinum = lymphatics and organs
Lymphatics = right lymphatic and thoracic ducts = drains into internal jugular + subclavian
Organs = trachea - ant to - eso
Describe contents of posterior mediastinum = venous
Venous = azygous (drains in sup, but located in post mediastinum) and hemi azygous system (post intercostal veins) = bypass svc and ivc, drains into base svc —> atrium, abdominal and thoracic wall
Describe contents of posterior mediastinum = nervous
Nervous = left and right vagus transitioning to anterior and posterior a gal trunks After hilum of lungs, respectively, with associated plexuses, sympathetic Chain, splanchnic nerves = 3
Describe contents of posterior mediastinum = lymphatics and organs
Lymphatics = thoracic duct - posterior
Organs = esophagus
