EKG Flashcards
1 small box?
1 mm = 0.04 seconds, 1 mV
1 large box?
5 mm = 0.2 seconds, 5 mV
Normal sinus rhythm?
Rate 60-100
P waves identifiable and of the same morphology throughout
RR intervals between beats are the same
Normal duration of P wave?
No more than 1 box wide
Normal voltage of P wave?
No more than 1 box tall
Best lead to look at P wave?
V1
If P wave exceeds the normal range for duration or voltage, what does this mean?
Either or both atria are hypertrophied
Q wave?
First downstroke (usually very small or absent)
R wave?
First upward deflection
S wave?
First downward deflection after the R wave
Normal QRS complex duration?
0.08-0.12 seconds
Prolonged QRS complex?
BBB
Drug toxicity
Electrolyte imbalance
Shortened QRS complex?
WPW
Q wave can be normal in what 2 leads?
III and aVR
When is a Q wave significant?
> 1 box wide in any lead except III and aVR
1/3 the amplitude of QRS
1/4 R wave
Indicates infarct