How to Read Basic EKG
- 1). Look at the first section of rhythm on the EKG. This interval shows a wave that usually looks like a little hill, then a break before a spike. This wave is called "P." (The waves noted on an EKG monitor are conveniently named alphabetically.) When the ECS begins electrical output at the top of the right atrium it flows through atria and is held for a moment before being dispersed through the ventricles after which the heart contraction occurs. This electrical insurgence into the atria causes interval "P." Note that from the start of the "P" wave to the start of the "QRS" is called the "PR" Interval. Normal PR Intervals are .12 to .20 seconds in length.
- 2). Look at the next wave. The "QRS" is the spiking interval on the EKG caused by electricity going through the ventricles (depolarization). It should be equal to or less than .10 seconds. On an EKG if the spikes are an even distance apart this indicates a regular ventricular rhythm.
- 3). See that right after the spike that there is a pause before another hill is shown. This is where the pulse occurs. The last hill in the series on the EKG is the "T Wave." It shows the recovery of the ventricles through repolarization.
- 4). Count 30 medium size boxes (ones with 25 little boxes inside) on the EKG graph paper starting with the box after a QRS spike. (This represents 6 seconds of time.) Count the number of spikes that occur within the 30 boxes. Multiply by 10. This gives you the ventricular rate (heart rate). Normal heart rate is 60 to 80 beats per minute. Then count the number of P intervals the same way for the PR rate. There should be one P Wave for every QRS.
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