cardiovascular Flashcards
electrical conduction in the heart
SA node
interstitial pathways
AV node
bundle of HIS
left and right bundle branches
purkinjie fibers
pathway of blood in the heart
SV
RA
tricuspid
RV
pulmonic SLV
pulm artery
capillaries/lungs
pulm vein
LA
mitral SLV
LV
aortic SLV
aorta
body
3 lead telemetry placement
white on right, smoke over fire
5 lead telemetry placement
white on right, clouds over grass, smoke over fire (on left) , brown to the ground (in the middle)
p wave represents
atrial depolarization
PR interval represents
atrial contraction
QRS complex represents
atrial repolarization and ventricular depolarization
ST segment represents
ventricular contraction
T wave represents
ventricular repolarization
QT interval represents
sum of ventricular activity
isoelectric line
imaginary line that is the baseline of electrical activity in the heart – neutral
what coronary artery is known as the widowmaker
LCA
what is DBP for adequate perfusion
60
if femoral pulse is palpable, SBP is greater than or equal to…
70
what is collateral circulation
formation of new blood vessels around area of decreased blood flow
bruit
sound when arteries are narrowed
automaticity
hearts ability to initiate an impulse spontaneously and continuously
conductivity
ability to transmit impulses to other areas in an orderly fashion
excitability
ability of cardiac cells to respond to a stimulus by initiating an impulse
refractoriness
the inability to respond to a stimulus by initiating an impulse
contractility
the physical ability to respond to an impulse by contracting or pumping
- the only one thats mechanical
what is inotropic
the force of contraction
positive inotropic drugs
digoxin, Calcium, dopamine, epi
negative inotropic drugs
BB, CBB, ETOH
lusitropic
ventricular relaxation
(diastolic function)
positive lusitropic drugs
catecholamines: epi, norepi, dobutamine, dopamine
negative lusitropic drugs
hypercalcemia
chronotropic
speed of SA node sending out impulses
positive chronotropic drugs
atropine, dopamine, epi
negative chronotropic drugs
digoxin, BB, Ach
dromotropic
speed of electrical conduction along conduction pathway (AKA muscle response or conduction velocity)
postivie dromotropic drugs
isuprel, phenytoin
negative chronotropic drugs
verapamil, adenosine
normal cardiac output
4-8L/min
normal stroke volume
60-100mL/beat
normal MAP
70-110
minimum MAP required for systemic perfusion
60
what is preload
the stretch on the right ventricle as blood comes IN to the heart
starlings law
increased stretch= stronger contraction
3 physical things and 2 drugs causing high preload
- increased volume
- venous congestion
- vasoconstriction
- dopmine and epi
2 physical and 1 med causing low preload
- decreased bld volume
- vasodilation
- NTG
what is afterload
the squeeze on the heart in order to pump blood out
causes for high afterload
vasoconstriction
HTN
aortic stenosis
causes for low afterload
vasodilation
