EKG Flashcards
What are the steps of EKG interpretation?
- Rate
- Intervals
- Axis
- Rhythm
- Hypertrophy
- Infarction / Ischemia
- Other
How do you determine rate?
Measure R-R intervals or count the # of complexes and multiply by 6
How do you measure rate using the RR interval?
use the 300 – 150 – 100 – 75 – 60 – 50 - 40
What are the intervals we measure?
PR, QRS, Qtc
What is the normal PR interval?
0.12 - 0.20 seconds
What does one “itty-bitty” box count for? what about one big box?
itty-bitty box = 0.04 seconds
big box = 0.20 seconds
What is the normal QRS interval?
0.06 - 0.10 seconds
What is the normal QTc interval?
0.30 - 0.46 seconds or as long as the Qt interval is less than half the preceding R-R interval
What is normal axis?
between -30 and 90
Where is the axis if lead I is positive and lead II is positive?
Normal axis! -30 to -90
Where is the axis if lead I is positive and lead II is negative?
left axis deviation! -30 to 270
Where is the axis if lead I is negative and lead II is positive?
right axis deviation! 90 to 150
Where is the axis if lead I is negative and lead II is negative?
no mans land! 150 to 270
PR interval more than 0.20 seconds with 1:1 conduction
1st degree AV block
PR interval lengthens followed by completely blocked P wave
2nd degree AV block type 1