ECG Basics 1

Question 1

Name what is happening at each step.

Answer 1

Question 2

On ECG paper

1 large block = ____ seconds

____ large blocks = 1 second

___ large blocks = 3 seconds

Answer 2

• 1 large block = 0.2 seconds, with each small box repreentnig 0.04 seconds
• 5 large blocks = 1 second
• 15 large blocks = 3 seconds

Question 3

1 small box measured vertically = ____

1 large box measured vertically = _____

2 large boxes measured vertically = _____

Answer 3

• 1 small box measured vertically = 0.1 mV
• 1 large box measured vertically = 0.5 mV
• 2 large boxes measured vertically = 1 mV

Question 4

For ventricular rhythms, examine the ______.

For atrial rhythm, examine the _______.

Answer 4

• R-R intervals
  
  • Q: Are they regular? Is each heart beats R-R interval equal?
• P-P intervals

Question 5

How do we calculate HR?

Answer 5

[Number of QRS complexes in 6 seconds] * [10]

Question 6

P wave

• NL amplitude:
• NL duration:

Answer 6

• NL amplitude: 0.05 to 0.25 mV (0.5 to 2.5 small boxes)
• NL duration: 0.06 - 0.11 seconds (1.5 -2.75 small boxes)

Question 7

PR interval indicates the ___________.

NL?

How is this affected as HR increases?

Answer 7

• AV conduction
• NL: 0.12 to 0.2 seconds (3-5 small boxes)
• Shortens as HR increases

Question 8

QRS wave: ventricular depolarization and contraction

• NL duration

Answer 8

0.08- 0.10 seconds

Question 9

T wave: ventricular repolarization

We should take note of what kind of T waves?

Answer 9

Downward (negative) deflection or ones with tall, pointed peaks.

Question 10

QT interval represents the time of_________

Answer 10

Ventricular depolarization + ventricular repolarization

-begining of QRS wave => end of T wave

Question 11

QT interval is _______seconds (_____ boxes)

Answer 11

0.36 to 0.44 seconds (9-11 boxes)

Question 12

ST segment represents the ______________

The ST segment is the line ___________

Answer 12

• ST segment represents the early part of ventricular repolarization.
• The ST segment is the line that from the end of the QRS complex to beginning of the T wave.