EKG- 30 common rhythms Final Test 2026\2027.
regular sinus
rate 60-100
regular
narrow QRS
upright P
PRI: .12-.20 seconds
QRS: .06 -.12 seconds
Sinus bradycardia
Rate: < 60 bpm
Every P has a QRS and every QRS has a P
PRI: .12 - .20 seconds
QRS: .8 - .12 seconds, narrow
sinus Tachycardia
Rhythm: regular/fast
Rate: > 100 bpm, below 150
Every P has a QRS and every QRS has a P
PRI: .12 - .20 seconds
QRS: normal
sinus arrhythmia
The irregular pattern of this rhythm fluctuates with inspiration (HR increases) and expiration (HR
decreases). A narrow QRS and upright P waves in Lead II is expected.
Sinus exit block
Sinus exit block (sinoatrial block) results from blocked sinus impulses - impulses not getting through to
depolarize the atria. While the sinus is firing on schedule, the tissue around the SA node is not carrying
the impulse. The seriousness of this dysrhythmia is related to the frequency and duration of the blocks.
Note that each pause is equal to a multiple of previous P-P intervals.
sinus arrest
occurs when the SA node fails to fire. The resulting pause is often NOT equal to the multiple of P-P
intervals seen in Sinus Exit Block. Instead, often an escape pacemaker such as the AV junction will assume
control of the heart. Again, like Sinus Exit Block, treatment is related to the frequency and duration of the
periods of sinus arrest.
NSR with PACs
Rhythm: Irregular with PAC's
Rate: dependent on rhythm
Every P has a QRS and every QRS has a P
, EKG- 30 common rhythms Final Test 2026\2027.
PRI: .12 - .20, may differ from underlying rhythm
QRS: dependent on rhythm
SVT
Rhythm: Regular
Rate: 150-250 bpm
PRI: Dependent on location of "circuit"
QRS: Normal, if accessory pathway used - prolonged (>.12) with delta wave (WPW)
A fib
Most common cardiac arrhythmia.
May occur with hypertension, ischemia, mitral valve and pericardial disease, MI, aging.
Increased risk for developing atrial thrombus and systemic embolism. Treatment includes
anticoagulation, drugs to slow ventricular conduction (rate control) and/or chemical or d/c
cardioversion.
Rhythm: irregularly irregular
Rate: slow or fast
No identifiable P's
QRS usually narrow but may be wide with conduction defect
A flutter
Characterized by "saw tooth" atrial activity
Conduction ratio to the ventricles 2:1 - 8:1. ( usually 2:1-4:1)
Caused by a reentrant circuit located in the right atrium.
May occur in COPD, hypoxia, intrinsic cardiac disease, valve disease, pericarditis or post operatively.
If >150 bpm, may seriously compromise cardiac output.
Treatment is rate control, cardioversion, surgical or catheter ablation.
Rate: atrial rate 250-400 (generally 300bpm)
A paced
results from the electronic pacing of an atrium. Note the vertical spike before the P wave. An electronic
pacemaker lead repeatedly generates a small but sufficient current to begin depolarization of the
atria...and the resulting P wave.
1st degree AV block
results from a prolonged transmission of the electrical impulse through the AV junction (AV node and the
Bundle of His). The significant finding of this rhythm is a prolonged PR interval of more than .20 seconds.
The underlying rhythm should be identified and named prior to claiming a first degree AV block. For
example, this rhythm is a normal sinus rhythm WITH a first degree AV block.
2nd degree AVB type 1
regular sinus
rate 60-100
regular
narrow QRS
upright P
PRI: .12-.20 seconds
QRS: .06 -.12 seconds
Sinus bradycardia
Rate: < 60 bpm
Every P has a QRS and every QRS has a P
PRI: .12 - .20 seconds
QRS: .8 - .12 seconds, narrow
sinus Tachycardia
Rhythm: regular/fast
Rate: > 100 bpm, below 150
Every P has a QRS and every QRS has a P
PRI: .12 - .20 seconds
QRS: normal
sinus arrhythmia
The irregular pattern of this rhythm fluctuates with inspiration (HR increases) and expiration (HR
decreases). A narrow QRS and upright P waves in Lead II is expected.
Sinus exit block
Sinus exit block (sinoatrial block) results from blocked sinus impulses - impulses not getting through to
depolarize the atria. While the sinus is firing on schedule, the tissue around the SA node is not carrying
the impulse. The seriousness of this dysrhythmia is related to the frequency and duration of the blocks.
Note that each pause is equal to a multiple of previous P-P intervals.
sinus arrest
occurs when the SA node fails to fire. The resulting pause is often NOT equal to the multiple of P-P
intervals seen in Sinus Exit Block. Instead, often an escape pacemaker such as the AV junction will assume
control of the heart. Again, like Sinus Exit Block, treatment is related to the frequency and duration of the
periods of sinus arrest.
NSR with PACs
Rhythm: Irregular with PAC's
Rate: dependent on rhythm
Every P has a QRS and every QRS has a P
, EKG- 30 common rhythms Final Test 2026\2027.
PRI: .12 - .20, may differ from underlying rhythm
QRS: dependent on rhythm
SVT
Rhythm: Regular
Rate: 150-250 bpm
PRI: Dependent on location of "circuit"
QRS: Normal, if accessory pathway used - prolonged (>.12) with delta wave (WPW)
A fib
Most common cardiac arrhythmia.
May occur with hypertension, ischemia, mitral valve and pericardial disease, MI, aging.
Increased risk for developing atrial thrombus and systemic embolism. Treatment includes
anticoagulation, drugs to slow ventricular conduction (rate control) and/or chemical or d/c
cardioversion.
Rhythm: irregularly irregular
Rate: slow or fast
No identifiable P's
QRS usually narrow but may be wide with conduction defect
A flutter
Characterized by "saw tooth" atrial activity
Conduction ratio to the ventricles 2:1 - 8:1. ( usually 2:1-4:1)
Caused by a reentrant circuit located in the right atrium.
May occur in COPD, hypoxia, intrinsic cardiac disease, valve disease, pericarditis or post operatively.
If >150 bpm, may seriously compromise cardiac output.
Treatment is rate control, cardioversion, surgical or catheter ablation.
Rate: atrial rate 250-400 (generally 300bpm)
A paced
results from the electronic pacing of an atrium. Note the vertical spike before the P wave. An electronic
pacemaker lead repeatedly generates a small but sufficient current to begin depolarization of the
atria...and the resulting P wave.
1st degree AV block
results from a prolonged transmission of the electrical impulse through the AV junction (AV node and the
Bundle of His). The significant finding of this rhythm is a prolonged PR interval of more than .20 seconds.
The underlying rhythm should be identified and named prior to claiming a first degree AV block. For
example, this rhythm is a normal sinus rhythm WITH a first degree AV block.
2nd degree AVB type 1
