cardiovascular system part 1 Flashcards
4 chambers of the heart
right and left atria, right and left ventricle
cardiac muscle (myocardium)
striated under involuntary control, intercalated disks
order of systemic circulation
heart arteries arterioles capillaries venules veins heart
pulmonary circulation
to the lungs
pulmonary arteries
only arteries to carry deoxygenated blood - blood to lungs
order of pulmonary circulation
heart pulmonary arteries lungs pulmonary veins heart
systole
phase of ventricular contraction
diastole
phase of ventricular relaxation
end-systolic volume
blood volume remaining in ventricles after contraction
end-diastolic volume
blood volume in ventricles prior to contraction
stroke volume
volume of blood ejected from left ventricle with heart contraction
ejection fraction
ratio of stroke volume to end-diastolic volume (higher when heart is full of blood and more efficient)
preload
end diastolic pressure when heart chambers are fully stretched during diastole (good thing)
afterload
resistance to heart pumping blood into circulation (ventricular emptying) which increases workload for the heart - it is bad if it is high
arteries
carry blood away from the heart that is oxygenated (except pulmonary arteries)
thick walled, elastic,
arterioles
smaller than arteries, much resistance, surrounded by smooth muscle, can change shape with vasoconstriction and dilation
capillaries
very small, RBCs pass one at a time for gas exchange and nutrient exchange
venules
empty into veins, size of arterioles
veins
low resistance
blood toward heart (deoxygenated except pulmonary veins)
smooth muscle
distensible with one way valves
bloop pressure
force exerted on blood vessel walls
Cardiac output x total peripheral resistance
systolic blood pressure
force that blood exerts on arterial walls during systole (120mmHg at rest)
Diastolic blood pressure
force that blood exerts on arterial walls during diastole (~80mmHg)
Mean arterial pressure (MAP)
mean blood pressure in arterial system
-DBP + [0.333 (SBP-DBP)]
which vessels have the largest diameter
arteries
which vessels have the largest total cross-sectional area?
capillaries
what factors influence blood pressure
cholesterol, age, elasticity, athlerosclerosis, diet, movement, heart rate, genetics, medication, vessel diameter, posture, altitude, health status, vessel length, peripheral resistance
3 sources of peripheral resistance
vessel diameter
blood viscosity
blood vessel length
blood pressure is highest in the ___
aorta
blood pressure is lowest in the ___ and ____ of heart
veins and right atrium
coronary circulation
blood returns to the right atrium via coronary veins
thrombus
blood clot
O2 consumption
a-vO2 diff x cardiac output
arterio-venous oxygen difference
difference in amount of oxygen returned in venous blood and the amount originally carried in arterial blood
Rate pressure product
myocardial oxygen consumption
RPP = HR x SBP
