APEX EKG Test/ 41 Questions with
Detailed Solutions & Diagrams.
Premature Atrial Contractions
PACs
Regularity: underlying atrial rate is regular except for early beat,
ventricular rate is regular
Rate: determined by the underlying rhythm
P wave: upright, smooth, round and uniform shape, EXCEPT for the
premature beat, it will shaped differently
PRI : 0.12 to 0.20 seconds except for early beat
QRS: 0.06 to 0.10 seconds and all are uniform
QTI: 0.36 to 0.46 seconds
T wave: upright, smooth and round uniform shape
Other: because the electrical stimulus is originating somewhere in the
atria (but NOT the SA node) it affects the P wave formation
Page 1 of 19
,EKG Grid
Each small square (the smaller lighter boxes within the big bold boxes)
represents 0.04 seconds
Each larger square (the boxes within the bold lines) represents 0.2
seconds.
Each large square has 5 small squares across SO 0.04 X 5 = 0.2 seconds
The 6 Second Strip Method
Least accurate, but quickest way to estimate rate especially in irregular
rhythms
EKG
Page 2 of 19
, EKG intervals
P Wave
Atrial depolarization
PR Interval
Normal is 0.12 to 0.20 seconds
Corresponds to the delay the AV node provides to allow for ventricular
filling
QRS Complex
Normal is <0.12 seconds usually between 0.06 to 0.10 seconds
Ventricular depolarization
QT Interval
Normal 0.36-0.46
6 Steps for Rhythm Interpretation
Page 3 of 19
Detailed Solutions & Diagrams.
Premature Atrial Contractions
PACs
Regularity: underlying atrial rate is regular except for early beat,
ventricular rate is regular
Rate: determined by the underlying rhythm
P wave: upright, smooth, round and uniform shape, EXCEPT for the
premature beat, it will shaped differently
PRI : 0.12 to 0.20 seconds except for early beat
QRS: 0.06 to 0.10 seconds and all are uniform
QTI: 0.36 to 0.46 seconds
T wave: upright, smooth and round uniform shape
Other: because the electrical stimulus is originating somewhere in the
atria (but NOT the SA node) it affects the P wave formation
Page 1 of 19
,EKG Grid
Each small square (the smaller lighter boxes within the big bold boxes)
represents 0.04 seconds
Each larger square (the boxes within the bold lines) represents 0.2
seconds.
Each large square has 5 small squares across SO 0.04 X 5 = 0.2 seconds
The 6 Second Strip Method
Least accurate, but quickest way to estimate rate especially in irregular
rhythms
EKG
Page 2 of 19
, EKG intervals
P Wave
Atrial depolarization
PR Interval
Normal is 0.12 to 0.20 seconds
Corresponds to the delay the AV node provides to allow for ventricular
filling
QRS Complex
Normal is <0.12 seconds usually between 0.06 to 0.10 seconds
Ventricular depolarization
QT Interval
Normal 0.36-0.46
6 Steps for Rhythm Interpretation
Page 3 of 19
