week 6 Flashcards
3 layers of vessels
tunica intima
tunica media
tunica externa
what layer is thickest in arteries
tunica media
whats in tunica adventitia
vasa vasorum (blood vessels)
whats the thickest layer in veins
tunica adventitia
elastic arteries
musclular arterises
arterioles metaarterioles
elastic- near heart for high pressure flow
muscular- smooth muscle throughout body (i.e. femoral artery)
arteriole- to capillary; regulate BP
metarteriols= control flow into capillaries
3 types of capillaries
continuous- least permeable , majority
fenestrated- filter and absorb (i.e. kidney)
sinusoidal- very permeable (i.e spleen, liver)
medium veins have
valves to prevent back flow in legs esp low prersusure
2/3 of body blood is in
systemic veins
smaller radius and increased vessel length and viscosity casue
more resistance
flow increases with
increased pressure and vessel radius
series vs parllale cicrculation
parallel good to reduce resistance; majority in body
compliance
how much pressure is required to change the diameter (volume) o
- High compliance: small amount of pressure ! large change in volume
▪ In general, veins are more compliant than arteries
decrease compliance; arteriosclerosis and calcification
what vasodilates arteries
O2, CO2, H+, lactate, adenosine, K+
Nitric oxide made from
l arginine
vasodilate and vasoconstrict
hitamine
bradykini
PG E2 and I2
E and NE via beta 2
constrict:
E and NE via alpha 1
serotonin
thromboxane
Angiotensin II
ADH
cushing reflex
increase intracranial pressure –> decreased perfusion
2 types of heart fialure
systolic dysfunction- HFrEF
–>impaired contractility - rely on elevated preload for adequate cardiac output
diastolic dysfunction- HFpEF
–> force of contraction ok, maybe impaired EDV
forward flow and back flow problem in heart failure
impaired cardiac output to tissue impair function
congestion and edema and
what has greatest afteload and first to fail
left ventricle
pulmonary microcirculation is opposite to other vasculature
in low oxygen it
constricts (to improve gas exhange)
concentric vs eccentric hypertrophy in heart failure
concentric- heart muscle thicken in response to increased pressure
eccentric- heart muscle enalrges, leads to decreased ejection fraction
BNP and ANP
heart failure will become resistance and they no longer lead to sodium and water loss
4 classes of heart fialure
class 1 physical activity is ok
2- good at rest but physical activity bad
4. heart fail
regurgitation
back flow across valve
▪ Incompetence (insufficiency) = the valve does not close completely
▪ Prolapse = excessive (backwards) valve movement into the proximal chamber
rheumatic fever is from
auto-immune reaction to infection with Group A streptococcus
rheumatic heart disease
The aortic valve lies between the left ventricles and the aorta. The mitral valve lies between the left atria and the left ventricle.
ok
