heart Flashcards
1
Q
floor of thoracic cavity
A
diaphragm
3 openings (hiatus):
- aorta
- inferior vena cava
- oesophagus
2
Q
3 spaces of thoracic cavity
A
- 2 lateral: plural cavities: contain lungs
- central (bit to the left): mediastinum: heart, oesophagus, trachea, lymph sinus
3
Q
mediastinum
A
walls:
- anterior: sternum: bone component
- inferior: diaphragm
- lateral: lungs
- posterior: thoracic vertebrae
- line divides superior and inferior regions: at sternal angle/T4-T5 disk
inferior:
- anterior, middle (heart), posterior (oe)
4
Q
relations of the heart
A
- superiorly: no proper relations, location of greater vessels
- anteriorly: thymus +sternum
- inferiorly: diaphragm
- posteriorly: oesophagus
- laterally: lungs
5
Q
heart shape
A
- pyramidal shape
- oblique position
- inferior apex orientated forward and down to the left
- superior base orientated upward and back
- main axis oblique: almost horizontal
- LV rotated posteriorly
- anterior/sternal surface
- posterior/diaphragmatic surface
- 2 lateral borders separate anterior and posterior surfaces: left is obtuse and right is acute
6
Q
anterior surface/aspect of heart
A
- superior region: greater vessels
- externally: auricles: external muscular extensions of atria: right larger, left smaller
- inferiorly: external muscular structures of ventricles
- mainly RV + small part of LV containing apex
- atrioventricular groove: horizontal groove goes around heart: division of As and Vs: passage of coronary vessels: coronary groove/sinus
- anterior interventricular groove: oblique vertical groove on external part of septum separating Vs
7
Q
greater vessels on anterior surface of heart
A
- bordered by auricles
- superior vena cava: end of general circulation: collect all venous blood from organs superior to diaphragm
- aorta: greater artery of circulatory system: beginning of general circulation: supply all organs and tissues with collateral branches: ascending anteriorly - arch -descending posteriorly
- pulmonary artery: starts of pulmonary circulation
8
Q
external posterior surface of heart
A
- superior and inferior region
- no auricles
- superior vena cava: continuation with inferior: vertical venous structure
- vertical straight portion of aorta curved to form the aortic arch: descending posteriorly
- pulmonary trunk splits into right and left pulmonary artery to right and left lung
- 4 pulmonary veins: 2 from each lung complete pulmonary circulation
- posterior interventricular groove: more vertical: passage of vessels
- terminal sulcus: joining of two vena cava
- crux cordis, coronary sinus
9
Q
pericardium
A
- sac
- separates heart from other organs
external fibrous layer: attachment of ligament connecting to other organs: - heart to diaphragm
- heart to sternum to maintain position: sternopericardial ligaments
internal serous layer: corresponds to epicardium: - epicardium: visceral PC
- middle: muscular
- endocardium: epithelium: single layer of squamous cells
10
Q
function of pericardium
A
- protects and anchors heart
- prevents overfilling
- allows heart to work in relatively friction free environment
11
Q
anatomy of pericardium
A
- double-walled sac around heart
- superficial fibrous pericardium
- deep two-layer serous pericardium:
- parietal layer lines the internal surface of the fibrous pericardium
- visceral layer of serous pericardium: epicardium: lines the surface of the heart
- separated by fluid-filled pericardial cavity
- foldings of pericardium onto heart follow large vessels
12
Q
heart wall
A
- epicardium
- myocardium
- endocardium
13
Q
visceral serous layer of pericardium
A
- outer layer: party of epicardium
- smooth muscle
- able to secrete fluid
14
Q
A
15
Q
moderator band of septomarginal trabecula
A
- septum + lateroinferior wall
- Leonardo’s
- 2nd order trabeculi: 2 different walls of ventricle
- specific myocardial tissue
- generates conduct stimulus: higher frequency than average tissues
