APEX EKG UPDATED EXAM SCRIPT QUESTIONS AND
ANSWERS RATED A+
✔✔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
✔✔Atrial Fibrillation - ✔✔Regularity: atrial and ventricular rate irregularly irregular
Rate:
Atrial rate: unable to determine they are beating in excess of 350 to 700 beats per
minute
Ventricular rate: when the HR is 100 or less beats per minute, the rate is said to be
"controlled"; if the ventricular rate is > 100 beats per minute then the rhythm is said to
have a RVR (rapid ventricular response)
P wave: absent, indiscernible, replaced by fibrillatory waves
PRI : indiscernible
QRS: 0.06 to 0.10 seconds
QTI: may be indiscernible
T wave: may be indiscernible
✔✔Atrial Flutter - ✔✔Regularity: atrial usually regular, ventricular rate may be irregular
depending on the conduction rate thru the AV node
Rate:
Atrial rate: 250 to 350 beats per minute
Ventricular rate: usually 60 to 150 beats per minute depending on the conduction thru
the AV node
P wave: abnormal, sawtoothed appearance known as "flutter waves", also described as
"picket fence shaped or V-shaped"
PRI : indiscernible, because there are no true P waves
QRS: 0.06 to 0.10 seconds
QTI: indiscernible
T wave: indiscernible
✔✔Atrial Tachycardia - ✔✔Regularity: R-R intervals are regular, overall rhythm is
regular
Rate: Atrial and ventricular rates are the same. The rate is usually between 160-250
beats/min
, P wave: There is one p wave in front of every QRS. The P waves may appear different
than a sinus P wave due to the rapid rate. They can be notched or flattened, and in
some cases the P wave may be lost within the QRS complex
PRI : 0.12 to 0.20 seconds, PRI is consistent, but may not be easily measured due to
the rate
QRS: 0.06 to 0.10 seconds and all are uniform
QTI: usually indiscernible
T wave: usually indiscernible
✔✔Supraventricular Tachycardia (SVT) - ✔✔Regularity: atrial and ventricular rate
regular
Rate: greater than 160 beats per minute, (can be 200 beats per minute or more)
P wave: abnormal, small and upright, may be hidden in QRS if rate is very fast
PRI : less than 0.12 seconds, if present
QRS: typically less than 0.06 - 0.08 seconds, very narrow
QTI: indiscernible
T wave: indiscernible
✔✔Paroxysmal Supraventricular Tachycardia (PSVT) - ✔✔Paroxysmal refers to a
rhythm that starts and stops suddenly
✔✔Premature Junctional Contractions - ✔✔Regularity: underlying rate is regular except
for early beat
Rate: determined by the underlying rhythm
P wave: upright, smooth, round and uniform shape, EXCEPT for the early beat, it will be
inverted before or after the QRS or missing
PRI : 0.12 to 0.20 seconds normal in the underlying rhythm, <0.12 seconds in the early
if it precedes the QRS
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
✔✔Junctional Rhythm - ✔✔Regularity: atrial and ventricular rate is regular
Rate: 40 to 60 beats per minute
P wave: inverted or absent, may be before, within or after the QRS
PRI : less than 0.12 seconds if the P wave precedes the QRS complex
QRS: 0.06 to 0.10 seconds and usually normal
QTI: 0.36 to 0.46 seconds
T wave: usually normal, upright, smooth and round uniform shape
✔✔Accelerated Junctional Rhythm - ✔✔Regularity: atrial and ventricular rate is regular
Rate: > 60 but less than 100
P wave: inverted or absent, may be before, within or after the QRS
PRI : less than 0.12 seconds if the P wave precedes the QRS complex
QRS: 0.06 to 0.10 seconds and usually normal
QTI: 0.36 to 0.46 seconds
ANSWERS RATED A+
✔✔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
✔✔Atrial Fibrillation - ✔✔Regularity: atrial and ventricular rate irregularly irregular
Rate:
Atrial rate: unable to determine they are beating in excess of 350 to 700 beats per
minute
Ventricular rate: when the HR is 100 or less beats per minute, the rate is said to be
"controlled"; if the ventricular rate is > 100 beats per minute then the rhythm is said to
have a RVR (rapid ventricular response)
P wave: absent, indiscernible, replaced by fibrillatory waves
PRI : indiscernible
QRS: 0.06 to 0.10 seconds
QTI: may be indiscernible
T wave: may be indiscernible
✔✔Atrial Flutter - ✔✔Regularity: atrial usually regular, ventricular rate may be irregular
depending on the conduction rate thru the AV node
Rate:
Atrial rate: 250 to 350 beats per minute
Ventricular rate: usually 60 to 150 beats per minute depending on the conduction thru
the AV node
P wave: abnormal, sawtoothed appearance known as "flutter waves", also described as
"picket fence shaped or V-shaped"
PRI : indiscernible, because there are no true P waves
QRS: 0.06 to 0.10 seconds
QTI: indiscernible
T wave: indiscernible
✔✔Atrial Tachycardia - ✔✔Regularity: R-R intervals are regular, overall rhythm is
regular
Rate: Atrial and ventricular rates are the same. The rate is usually between 160-250
beats/min
, P wave: There is one p wave in front of every QRS. The P waves may appear different
than a sinus P wave due to the rapid rate. They can be notched or flattened, and in
some cases the P wave may be lost within the QRS complex
PRI : 0.12 to 0.20 seconds, PRI is consistent, but may not be easily measured due to
the rate
QRS: 0.06 to 0.10 seconds and all are uniform
QTI: usually indiscernible
T wave: usually indiscernible
✔✔Supraventricular Tachycardia (SVT) - ✔✔Regularity: atrial and ventricular rate
regular
Rate: greater than 160 beats per minute, (can be 200 beats per minute or more)
P wave: abnormal, small and upright, may be hidden in QRS if rate is very fast
PRI : less than 0.12 seconds, if present
QRS: typically less than 0.06 - 0.08 seconds, very narrow
QTI: indiscernible
T wave: indiscernible
✔✔Paroxysmal Supraventricular Tachycardia (PSVT) - ✔✔Paroxysmal refers to a
rhythm that starts and stops suddenly
✔✔Premature Junctional Contractions - ✔✔Regularity: underlying rate is regular except
for early beat
Rate: determined by the underlying rhythm
P wave: upright, smooth, round and uniform shape, EXCEPT for the early beat, it will be
inverted before or after the QRS or missing
PRI : 0.12 to 0.20 seconds normal in the underlying rhythm, <0.12 seconds in the early
if it precedes the QRS
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
✔✔Junctional Rhythm - ✔✔Regularity: atrial and ventricular rate is regular
Rate: 40 to 60 beats per minute
P wave: inverted or absent, may be before, within or after the QRS
PRI : less than 0.12 seconds if the P wave precedes the QRS complex
QRS: 0.06 to 0.10 seconds and usually normal
QTI: 0.36 to 0.46 seconds
T wave: usually normal, upright, smooth and round uniform shape
✔✔Accelerated Junctional Rhythm - ✔✔Regularity: atrial and ventricular rate is regular
Rate: > 60 but less than 100
P wave: inverted or absent, may be before, within or after the QRS
PRI : less than 0.12 seconds if the P wave precedes the QRS complex
QRS: 0.06 to 0.10 seconds and usually normal
QTI: 0.36 to 0.46 seconds