Exam 2 Flashcards
What is the first thing estimated when plotting a treadmill or bike submax test?
Estimated max workload
What are the assumptions that allow us to predict VO2max?
Max HR can be predicted accurately
A linear relationship exists between HR, workload, and VO2max.
VO2max is the same at any given workload.
What is occurring at the P wave?
Atrial contraction
SA node begins electrical impulse, which spreads in wave motion, stimulating atria and sets heart rate
What is the PR segment?
Flat line between P wave and Q wave
When the impulse reaches the AV node but there is a 1/10 second pause before impulse stimulates AV node so blood can enter ventricles
What is the QRS complex?
Made up of R, S and sometimes Q wave
Ventricular contraction
Impulse travels from the AV node down the AV bundle, to left and right bundle branches.
Left ventricle sends blood to the
Body
Right ventricle sends blood to the
Lungs
ST segment
Flat line between QRS complex and T wave
Pause before ventricles repolarize so they can contract again
T wave
Ventricle repolarization
What are the 6 limb leads?
I, II, III, aVR, aVL, and aVF
What view do the limb leads provide?
Frontal
What are the 6 chest leads?
V1, V2, V3, V4, V5, V6
What view do the chest leads provide?
Horizontal
What are the normal EKG responses to exercise?
P-wave had increased magnitudes among inferior leads
PR segment shortens and slopes downward among inferior leads
QRS duration decreases
J point depresses below isometric line with upsloping DT segments
T wave decreases in amplitude in early exercise and returns to preexercise intensities
QT interval decreases
What are the 6 steps if interpreting EKG data?
Heart rate Rhythm Calculating intervals Axis ST segment and abnormal waves Hypertrophy
What are the two ways to interpret heart rate?
On a machine
With a ruler
What is tachycardia?
Fast HR
Greater than 100 bpm
What is bradycardia?
Slowed heart rate
Less than 60 bpm