heart 2 Flashcards
stroke volume
the amount of blood ejected by each ventricle during a single beat - avg 80ml
stroke volume =
end diastolic volume - end systolic volume
EDV - ESV
diastole
relaxation of heart ventricles to fill
systole
a period of contraction in a chamber of the heart as part of the cardiac cycle
dicrotic notch
a valley in the pressure tracing caused by the elastic arterial walls recoiling after lunar valves close
left and right coronary arteries originate
base of aorta
infarction
an area of dead cells due to lack of blood flow
shortest circulatory route
coronary circulation 8 seconds
largest blood vessel
inferior vena cava
intrinsic conductive system
ability of the cardiac muscle to contract on its own in the absence of neural or hormonal stimulation
sinoatrial node
contains pacemaker cells which establish the heart rate
atrioventral node
delays signal and relays to apex to initiate contraction
ekg waves
electricity chart of heart p, q, r, s, t
p wave
depolarization of the atria
qrs complex
depolarization of the ventricles (repolarization of atria masked)
t wave
ventricles repolarize
isovolumentric contraction
period of ventricle contraction after av valves have closed but semilunar valves have not yet opened
Cardiac output
Stroke volume x pulse (amount of blood that can be pumped in one minute)
Mean Arterial Pressure (MAP)
((systolic-diasolic)x .3) + diastole
lubb
sound of AV valves closing
dubb
sound of semilunar valves closing
parasympathetic ACH’s affect on heart rate
slows
sympathetic affect on heart rate
NE - increase; NE and E in blood increase longer lasting
sympathetic affect on stroke volume
increases volume - greater force results in lower end systolic volume increasing stroke vol
cutting vagus nerve
increases heart rate
