General, Week 1 Cardio Block Flashcards
volume of blood that leaves the L ventricle per minute =
cardiac output
volume of blood that leaves the L ventricle per beat =
stroke volume
equation for cardiac output =
CO = SV x HR
ejection fraction:
percentage that leaves the L ventricle
Afterload:
pressure the L ventricle has to overcome for the blood to be ejected
inotropy:
force of contraction
Preload definition:
pressure of the L ventricle prior to contraction (closely related to volume of blood in L ventricle prior to contraction)
the remnants of the fossa ovalis is in what chamber of the heart?
the right atrium
what is the muscle called in the R atrium?
what separates this from the smooth muscle?
pectinate muscle
crista terminales (ridge on inside)
name the valve between the R atrium and R ventricle
right AV valve (tricuspid valve)
the _________ muscles attach to the flaps of the tricuspid valve via _____________. What are the purpose of these muscles?
papillary, via the chord tendinae
to keep the valve from prolapsing back into the atria during contraciton
the ___________ ________ is a branch off the trabecular carnae and is important for the conduction system into the ventricles
moderator band
what is the muscle called of the R ventricle wall?
trabecular carnae
what is the valve connecting the left atrium and left ventricle?
the left AV valve or MITRAL VALVE
what produces the regular rhythm of the heart?
sinoartrial (SA) node
name the three layers (think histo) of the heart
- endocardium
- myocardium
- epocardium (visceral pericardium)
describe the histology of a heart valve
a core of connective tissue lined on both sides by endocardium
___________ Smooth Muscle: individual smooth muscle cells controlled independently
(gap junctions are sparse)
___________ Smooth Muscle: cells work together as a single entity due to lots of gap junctions
multiunit
unitary
what are the two ways in which the SR in smooth muscle is activated to release Ca++?
IP3 binding
CICR
depletion of Ca++ from the SR in smooth muscle activates _________________, which do what two things?
store-operated Ca++ channels (voltage-independent)
restore Ca++ in SR, supplies contraction
contraction of smooth muscle is determined by the balance of phosphorylation/dephosphorylation of ______
MLC (myosin light chain)
Determinants of cardiac output = ______________________
heart rate and stroke volume
equation for cardiac output using its two main determinants:
CO = HR x SV
equation for MAP (mean arterial pressure)
MAP = CO x TPR (total peripheral resistance)
the parasympathetic input to the heart is via the _________ nerve, which releases what NT and causes what to happen to the HR?
Vagus
Ach
decreases
the sympathetic input to the heart is via the __________________ nerves, which release what NT? what does this cause in the heart?
right and left stellate ganglia
NE
increase HR, increase contractility (2 ways)
what are the determinants of TPR (total peripheral resistance) of the blood vessel system?
Blood viscosity
Cross sectional area
Length of peripheral circuit
the prime determinant of the vascular resistance is the _____________.
arteriolar radius
the blood viscosity and length of tubes is held constant under normal conditions
the arterial blood pressure is regulated moment to moment by continuous adjustments to both the ____________ and ______________ via ___________________.
what about long term regulation?
cardiac output
total peripheral resistance
via the baroreceptor reflex
long term = blood volume
where are baroreceptors located?
arch of the aorta and the carotid sinuses
blood volume is regulated through the
renin-angiotensin system
what does aldosterone do in terms of blood pressure regulation?
it increases Na+ resorption in the kidneys, increasing blood volume and increasing blood pressure
what does angiotensin converting enzyme (ACE) do?
converts angiotensin 1 to angiotensin 2
angiotensin 2 produces aldosterone
when a decrease in arterial pressure is sensed by the renal arterioles, what is the cascade that happens?
prorenin –> renin –> angiotensin –> angiotensin 1 –> ACE –> angiotensin 2 –> aldosterone, vasoconstriction (increases TPR)
explain the things governing transcapillary solute exchange:
- concentration difference of solute
- permeability of the solute across the capillary
- SA for exchange
hydrostatic pressure in capillaries favors:
oncotic pressure in capillaries favors:
filtration
re-absorption
________ is when the hydrostatic pressure pushes liquid out of capillaries
filtration
the arterial side of the capillary favors ________ since the __________ pressure gradient is largest
the venous side of the capillary favors _______ since the _______ pressure gradient is largest
filtration, hydrostatic
reabsorption, oncotic
edema occurs when the net ________ of fluid from blood to tissues exceeds the capacity of the ___________
filtration, lymphatics
4 functions of lymphatic system
Return of excess filtered fluid
Immune defense
Transport of absorbed fat
Return of filtered protein
increasing venous return increases ________________ volume, which increases _______ volume, which increases cardiac output
end-diastolic
stroke
what are the 5 things that aid in venous return:
- cardiac suction during contraction
- Skeletal muscle
- Vein valves
- Sympathetic induces “vasoconstriction”
- Respiratory activity
increased venous blood volume ________ the venous return curve
decreased vascular tone __________ the venous return curve
increases
decreases
the only autonomic innervation of the adrenal gland is from the ___________ nervous system
what does it secrete when stimulated?
sympathetic
epinephrine
the only autonomic innervation of blood vessels is from the ________ nervous system and causes what?
sympathetic
vasoconstriction
aldosterone causes what to happen molecularly? in terms of blood pressure?
sodium retention and potassium secretion in the collecting tubules
increase blood volume and increase blood pressure
aldosterone is secreted from the _____________ in response to _________ or ______________
adrenal cortex
angiotensin 2 or high K+ levels
a decrease in arterial renal pressure causes ________ to be converted to _______, which then converts ____________ to ____________. ACE then converts ___________ to _____________
prorenin –> renin
angiotensinogen –> angiotensin 1
angiotensin 1 –> angiotensin 2
