cardiac Flashcards
(24 cards)
pericardium layers
fibrous
serous
what chamber is hard to see in an anterior view
left atrium
pacemaker cell resting membrane potential and maintenace
-70 and maintained by potassium
funny channel
when cell is hyperpolarised it opens to allow sodium in to hit threshold
what occurs at threshold for pacemaker cells
voltage gated calcium channels open
after depolarisation in pacemaker cells
calcium inactivated and potassium open (voltage sensitive)
atrial myocytes depolarisation
come from threshold being met through gap junctions leading to sodium channels opening
calcium plateau
not sufficient to contract, instead activates calcium induced calcium release
calcium removal
pumped back by SERCA
blood vessel layers
adventitia, media, intima
hydrostatic pressure
forces fluid out of the capillary
osmotic pressure
movement of fluid from the interstitial fluid into the capillary
EDV
120mL
SV
70mL
ESV
50mL
ejection fraction
SV-EDV
increasing preload
increases EDV, increases, increases afterload, induces baroreceptor reflex to slow HR
afterload
contraction must overcome pressure, less blood ejected, ESV higher
calcium released from
sarcoplasmic reticulum from ryanodine receptors
muscle contraction
calcium on troponin on thin filaments, pulls on tropomyosin to expose binding sites
chest X-ray view
posterior anterior to minimise heart shadow
triangular spaces between diaphragm and thoracic wall
costophrenic angles and should be sharp
inspiration chest x-ray
ribs will be horizontal and descended diaphragm
tract from baroreceptor to medulla
glossopharyngeal and vagus
