lab 3- 12 lead Flashcards
transducer
device for changing one form of energy into another
depolarization toward a positive electrode
upward wave
depolarization toward a negative electrode
downward wave
repolarization toward a positive electrode
downward wave
repolarization toward a negative electrode
upward wave
ground electrode
right leg, not used to record EKG
V1
4th intercostal, right side of sternum
V2
4th intercostal, left of sternum
V3
slightly to the left of V2, closer to V4
V4
5th intercostal space, directly below nipple
V5
5th intercostal space, anterior axillary line
V6
left mid-axillary line
frontal plane
1, 2, 3
aVR, aVL, aVF
transverse plane
V1-V6
best leads to look at left ventricle
1 and V5
bipolar limb leads in frontal plane
used to determine the vertical electrical axis of the cardiac impulse as it passes through the heart
leads 1, 2, 3
einthoven’s triangle
aVR
augmented voltage right (arm)
recording electrode=
positive electrode in that lead
aVL
augmented voltage left (arm)
aVF
augmented voltage foot (left leg)
augmented/unipolar limb leads in frontal plane
aVF aVR aVL
unipolar chest leads in transverse plane
V1-V6
mean QRS vector
mean electrical axis of the current flow as it passes through the ventricles
why are chest electrodes said to be unipolar?
only electrode that is able to read variations in the cardiac impulse as it passes through the heart
normal range of deviation
-30 to 90
RAD
90- 180 thickening of RV right ventricular hypertrophy dextrocardia old left ventricular MI
LAD
-90 - 0
left ventricular hypertrophy
high BP
old right ventricular MI
XRAD
180 - (-90)
scarring or lesion in a bundle branch
