Exam 4 - Lecture 5 Flashcards
in augmented leads, a stands for
augmented
aVR means
augmented, voltage, right arm has positive electrode
aVL means
augmented, voltage, left arm has positive electrode
aVF means
augmented, voltage, left foot has positive electrode
Augmented leads are ____ positive electrode, and ____ negative electrode.
One; Two
what would aVR read with a normal healthy heart during contraction? Where is the “negative” electrode?
negative deflection, since its running perfectly away from the positive electrode in the left arm.
it uses the middle area directly between left arm electrode and left leg electrode.
What lead would be able to look right between lead II and Lead III?
aVF
What degree angle is between standard leads and augmented leads?
30 degrees
aVR used leads at ____ and ____ to gather information
Left arm and left foot
aVL uses leads at ___ and ___ to gather information
Right arm and left foot
aVF uses leads at ___ and ____ to gather information
Right arm and left arm
aVF is using the positive or negative charge from which limbs?
Positive charge from the foot, and the negative average charge of the right and left arm
aVR is using the positive or negative charge from which limbs?
Positive right arm, and using the negative average charge from the left arm and the left foot.
aVL is using the positive or negative charge from which limbs?
Positive left arm, and using the negative average charge from the right arm and left foot.
All of the V-leads use _____ as the negative electrodes.
The negative charges of the limb-leads. Right arm/left arm, left foot.
V-leads are also called
precordial chest leads
Leads V1 and V2 are called what and located where?
Septal leads, each side of sternum in 4th intercostal space.
Leads V3 and V4 are alled what and located where?
Anterior leads, V4 is the 5th intercostal space to left side of heart
Leads V3 is sandwiched between Lead V4 and lead V2.
Leads V5 and V6 are called what and located where?
Lateral leads, 5th intercostal space to left side of heart
Which precordial lead should have the biggest deflection?
V4, most in line with MEA in healthy heart
Which precordial leads are mostly negative?
V1 and V2
Vectorcardiogram
used a long time ago, analyzed with a oscilloscope.
Reads the electrical activity of the heart as it depolarizes the ventricles. How its going down at 70 degrees at first, then more at 60, then less at 45, then the least at 30 degrees (degrees are randomized, but this is the direction of the numbers ordered)
Inverted t-wave means the
tissues arent repolarizing normally
If lead I and III are larger than lead II, is this a normal EKG?
No. Lead II should have the largest deflection, so there must be an axis deviation.
Do the ventricles depolarize at the same time?
yes, for the most part
If there is a resistor in the left bundle branch, what would the MEA look like? What does a resistor look like?
up and towards the left, cause the left ventricle is taking a long time to depolarize, skewing the MEA in its direction. Squiggly lines.
If its 5 big boxes up, and 1 big box down, how many net mV is the QRS?
2 mV
A large positive QRS in lead III could indicate?
hypertrophy in the right ventricle
Its large, so it takes more electrical current.
A current of injury means
theres a current coming from injured tissue that is constantly depolarizing instead of repolarizing, causing an abnormal current
