Intro To EKG

Question 1

When SA node fires, AP spread in all directions through the atrial myocardium

Answer 1

Yep

Question 2

When is there a maximum amplitude of signal when depolarization

Answer 2

Vectors along the axis

Question 3

Vector is placed at a right angle (perpedicular)

Answer 3

Zero amplitude

Question 4

Are limbs leads bipolar?

Answer 4

Yep

Question 5

P wave

Answer 5

Atrial depolarization immediately following SA node firing

Question 6

QRS complex

Answer 6

Ventricular depolarization plus atrial repolarization

Question 7

T wave

Answer 7

Repolarization of the ventricles

Question 8

P-R interval

Answer 8

~0.12-2 sec and it is the time that the signal is proceeding to the beginning of the QRS complex

Question 9

P-R segment

Answer 9

Time to pass through the AV node

Question 10

QRS interval

Answer 10

~0.06-0.1 sec and it is the duration of ventricular depolarization

Question 11

ST segment

Answer 11

Corresponds to plateau phase of ventricular AP

Question 12

QT interval

Answer 12

~0.2-0.4 sec and it is the duration of the ventricular AP

Question 13

Length of the vector is related to the

Answer 13

Mass of muscle tissue depolarizing at that instant

Question 14

Each vector points in the direction of

Answer 14

AP propagation

Question 15

Mean electric axis

Answer 15

Average of all the instantaneous vector

Question 16

Each positive lead is referenced against a combination of the other electrodes

Answer 16

Unipolar

Question 17

Augmented leads and limb leads detect electrical changes in the

Answer 17

Frontal plane

Question 18

Precordial leads measure dipoles in the

Answer 18

Horizontal (transverse) plane

Question 19

Middle of the great is the ______ connection

Answer 19

Negative

Question 20

Normal range of the mean electrical axis is from

Answer 20

30 - (+90)

Question 21

Left axis deviation

Answer 21

Less than -30 degrees

Question 22

Right axis deviation

Answer 22

More than +90 degrees