Cardiovascular System Flashcards
where is a catheter usually inserted from?
- radial or femural artery
Three types of aneurysm
- cerebral
- thoracic
- abdominal
heart germ layer origin
- visceral lateral plate mesoderm
heart structural origin
- primary and secondary heart fields -> heart tube
when does the heart begin developing?
- day 16
what do ‘fields’ in the early heart develop into?
- endocardial tubes
when does the heart start beating?
- day 22
what causes the caudal and cranial heart tubes to form the atria, ventricles and outflow track?
- cardiac looping
what does the truncus arteriosus form? (2)
- aorta
- pulmonary trunk
what does the bulbus cordis form? (2)
- right ventricle (trabeculated part = proximal)
- ventricle outflow tracts
what does the primitive ventricle form?
- left ventricle (trabeculated part)
what does the primitive atrium form?
- right and left atrium (trabeculated parts)
what does the sinus venosus form?
- right atrium (smooth parts)
how many days does cardiac looping occur?
- between days 22 and day 28
atrial septation steps (3)
- septum primum descends - from roof of atrium, leaves lumen
- ostium primum closes - but foramen secundum secundum forms via apoptosis in septum primum
- septum secundum forms - foramen ovule persists
what is atrial septal defect-secundum?
- large hole is atrial septum
cause of atrial septal defect? (2)
- too much cell death/reabsorption
- inadequate formation of septum secundum
what is the outer layer of the heart called?
- pericardium
what does the pericardium do?
- stabilises the heart and associated vessels within the mediastinum
how many layers is the pericardium made of?
- 2
mediastinum definition
- the space that holds everything in the thorax except the lungs
what is the outermost layers of the pericardium and its features?
- fiborus pericardium
- thick fibrous layer that contains collagen fibres
what is the innermost layer of the pericardium and its functions?
- serous pericardium
- balloon layer in contact with heart wall = visceral pericardium
- layer in contact with fibrous pericardium = parietal pericardium
define epicardium
- very thin external layer formed by the visceral layer of the serous pericardium
define myocardium (2)
- cardiac muscle layer
- containing blood vessels and nerves
define endocardium (3)
- covers inner surfaces of heart
- simple squamous epithelium
- areolar tissue
what is the smooth thin posterior wall of the right atrium called?
- sinus venarum
what is the rough muscular anterior wall of the right atrium called?
- pectinate muscle
right atrium features (4)
- sinus venarum - smooth thin posterior wall
- rough muscular anterior wall - pectinate muscle
- opening of the SVC, IVC and coronary sinus
- fossa ovalis
what is the fossa ovalis in development?
- foramen ovali
tricuspid valve features (4)
- three cusps
- allows blood to pass from right atrium to right ventricle
- prevents blood from regurgitating from the right ventricle back into the right atrium
- attached to chordae tendinae
what are chordae tendineae?
- heart strings
what do the chordae tendineae attach to?
papillary muscles
right ventricle key features (6)
- thinner muscular wall compared to the left
- valve cusps attach to chordinae tendineae
- chrordinae tendonae attach to papillary muscles
- trabeculae carneae lines the walls of both ventricles
- acts to increase turbulence of blood
- sends blood towards pulmonary trunk via pulmonary valve
pulmonary valve other name
- semilunar valve
left atrium key features (3)
- left auricle - contains pectinate muscles
- most of atrial wall is smooth
- slightly thicker wall than the right atrium
bicuspid valve other name
- mitral valve
bicuspid valve key features (4)
- two cusps (mitral valve)
- allows blood to pass from left atrium to left ventricle
- prevents blood from regurgitating from the left ventricle back into the left atrium
- attached to chordae tendineae
left ventricle key features (4)
- thick muscular walls
- thick mesh of trabeculae carneae muscle, more numerous than the right ventricle
- chordae tendineae attach to 2 papillary muscles
- sends blood towards aorta via aortic valve
aortic valve and blood flow features (3)
- origin of coronary arteries branches of the ascending aorta as the ventricles relax
- aortic valve closes
- blood pools in aortic sinuses
how big is the aorta in diameter?
- 3cm
aorta sections (4)
- ascending aorta
- aortic arch
- descending aorta
- abdominal aorta
what does the abdominal aorta bifurcate into?
- right and left common iliac arteries
how many branches does the aortic arch have?
- 3 but can be variable
what is systole?
- contracting
what is diastole?
- filling/relaxing
where is the sinoatrial node?
- located at the junction of the superior vena cava
what is the sinoatrial node?
- pacemaker of heart
what does the sinoatrial node do?
- initiates and regulates heart contractions
what does the impulse from SA node do?
- spreads electrical impulses through atria
where is the atrioventricular node located?
- interatrial septum
where does the AV node get its signal from?
- rapidly from the SA node
where does the AV node distribute signals to?
- ventricles through AV bundle
what is the AV bundle a bridge between?
- atrial and ventricular myocardium
where and what does the AV bundle divide into?
- right and left bundle branches
- once it reaches the IVS
what does the right bundle branch extend to and what does that stimulate? (2) MB
- the moderator band
- stimulates the right anterior papillary muscle
what does bundle branches ramify into?
- purkinjie fibres
- extend into the walls of the ventricles
the lungs are ___ to the heart
lateral
the diaphragm is ___ to the lungs
inferior
what is an incidental finding?
- incidentally discovered mass or lesion
- detected by CT, MRi, other imaging
which vertebral level would you palpate to examine aortic pulse?
- at or slightly above the umbilicus in the epigastrium
- supine position with knees bent
