COMPONENTS OF THE NORMAL ELECTROCARDIOGRAM Flashcards Preview

zz CVPR > COMPONENTS OF THE NORMAL ELECTROCARDIOGRAM > Flashcards

Flashcards in COMPONENTS OF THE NORMAL ELECTROCARDIOGRAM Deck (20):
1

atrial depolarization wave

P wave

2

ventricular depolarization wave

QRS complex

3

ventricular repolarization wave

T wave

4

EKG Leads

Leads are electrodes which measure the difference in electrical potential between either bipolar or unipolar

5

HR = 300 ÷ # heavy lines between 2 QRS’s

Calculation for HR on EKG

ex:
(300/6 boxes)= 50 BMP

6

Depolarization moving toward a positive electrode produces a ______ deflection

positive

and vice versa

7

QRS will be upright (+) in ______ leads
And downward (-) in right-sided leads

left and lateral

8

Leads: Two different points on the body

bipolar leads

std limb leads I, II, III

9

Leads: One point on the body and a virtual reference point with zero electrical potential, located in the center of the heart

unipolar leads

V1-V6
aVR
aVL
aVF

10

QRS will be upright (+) in left and lateral leads
And downward (-) in ________

right-sided leads

11

Ischemia occurs when blood supply is insufficient to meet:

oxygen demand in the ventricles

12

Ischemia due to sudden high oxygen demand (under stress) in the presence of fixed coronary obstruction causes:

depression of the ST segment

13

Ischemia due to acute coronary artery obstruction (at rest) during low oxygen demand causes:

T wave inversion

14

ST elevation is a sign of

TRANSMURAL CURRENT OF INJURY
Can be Tissue damage MI
Is reversible

15

1- PEAKED T-WAVE
2- T-WAVE INVERSION
3- ST ELEVATION
or
Q-WAVE
ST-ELEVATION
T-INVERSION

Caused by?

EVOLVING TRANSMURAL MYOCARDIAL INFARCT

16

MYOCARDIAL INFARCT
Transmural vs Subendocardial

Subendocardial:
ST depression
no Q wave

Transmural:
ST elevation
with Q waves

17

PROLONGED QT INTERVAL
Causes:

Hypocalcemia, hypokalemia, hypomagnesemia
Class 1A or 3 anti-arrhythmic drugs
Hypothermia
Congenital Long QT syndrome

18

The QT interval is more than half the RR interval says________

PROLONGED QT INTERVAL

19

Hypercalcemia causes on ECG

Shortened QT

20

Hypocalcemia causes on ECG

Prolonged QT