Dubin Book Notes Flashcards
True or False: Q waves are often absent on the EKG?
True
a QT interval is considered normal when it is less than what?
half the R to R internal at normal rates
the movement of which ions control the following: cardiac contraction? cardiac conduction (AV node and SA node)? cardiac repolarization?
ca++, Av node is ca++ sa node is na+ and K+ for repolarization; note cell to cell conduction of depolarization through myocardium is carried by Na+ ions!!
what are your chest leads known as?
V1-V6; theses are also known as precordial leads
what are your limb leads?
I, II, III and AVR, AVL, and AVF
which are your bipolar limb leads?
I, II, II
which are your augmented leads and what do they stand for?
AVF, AVR, AVL - augmented voltage right arm, left foot, left arm
which leads are sometimes called your unipolar leads and why?
augmented limb leads - AVR, AVL, AVF -they are all simply positive - right arm, left arm and left foot respectively
which are your lateral leads?
I and AVL - why? b/c each of these has a + electrode positioned laterally on the left arm
which are your inferior leads?
II, III, and AVF - why? b/c each of these has a positive electrode positioned inferiorly in the left foot
what is the charge on the suction cup electrodes that are places on the chest/heart? (these leads are your chest leads V1 - V6)
positive
because the electrodes for the chest leads are always + how will a depolarization wave moving towards the chest be depicted on the EKG?
positive (upward) deflection on the EKG tracing in that chest lead
the chest leads are oriented through what structure of the heart? they then project where and are what charge once projected?
AV node; towards patient’s back and are negative
which of the chest leads is described as a straight line directly from the front to the back of the patient?
V2
which are your right chest leads?
v1 and v2
