Dysrhythmia Interpretation
ECG analysis involves the assessment of the following factors:
Rhythm: Measure P-P and R-R intervals to determine whether the intervals are regular.
If irregular, is there some pattern to the irregularity?
Rate: Calculate the rate of P and R waves. A normal rate falls between 60 and 100 complexes per
minute (count the number of R waves over 6 seconds and multiply by ten).
P waves: Check to see whether P waves are present before each QRS complex, that each P
wave looks similar in size and shape, and the waveform is upright (positive deflection) in Lead
II. The P waves should also maintain a consistent appearance.
P-R interval: The normal interval is between 0.12 and 0.2 seconds, and is constant.
QRS complexes: All complexes look similar and are predominantly positive. Each QRS
complex should be no more than 0.1 seconds wide (some texts state 0.12 seconds).
Classifying the rhythm
Rhythms can be generally classified under the following categories:
Sinus Rhythm Rate P wave P-R interval QRS complex
Sinus rhythm Essentially regular 60-100 Normal, precede 0.12-0.20 & Normal (0.10 or
each QRS constant less)
Sinus Regularly irregular 60-100 Normal, precede 0.12-0.20 & Normal (0.10 or
dysrhythmia each QRS constant less)
Sinus Essentially regular < 60 Normal, precede 0.12-0.20 & Normal (0.10 or
bradycardia each QRS constant less)
Sinus Essentially regular > 100 - Normal, precede 0.12-0.20 & Normal (0.10 or
Tachycardia 180 each QRS usually less)
constant
Sinoatrial Exit Irregular when Normal, precede 0.12-0.20 & Normal (0.10 or
Block block is present each QRS usually less)
QRS pause IS 60-100 No P wave when constant May be wide if
multiple of P-P block occurs a conduction
interval defect exists
Sinus Arrest Irregular due to the Normal, precede 0.12-0.20 & Normal (0.10 or
pause each QRS usually less)
QRS pause is NOT 60-100 No P wave when constant May be wide if
multiple of P-P arrest occurs a conduction
interval defect exists
Atrial Rhythm Rate P wave P-R interval QRS complex
Supraventricular Essentially regular 160- Present or 0.12-0.20 if Usually normal
tachycardia 240 absent. May be pacemaker is in (0.10 or less)
up-right or the atria, or less
(Atrial inverted than 0.12 if
Tachycardia) depending on pace site is
the origin. lower. May
also occur after
the QRS.
Atrial flutter Usually regular Atrial Not seen (F N/A Usually normal
rate av. waves are saw- (0.10 or less)
300 toothed)
V rate
av. 150
This study source was downloaded by 100000851739762 from CourseHero.com on 09-09-2022 05:01:35 GMT -05:00
https://www.coursehero.com/file/23492163/Dysrhythmia-interpretation/
ECG analysis involves the assessment of the following factors:
Rhythm: Measure P-P and R-R intervals to determine whether the intervals are regular.
If irregular, is there some pattern to the irregularity?
Rate: Calculate the rate of P and R waves. A normal rate falls between 60 and 100 complexes per
minute (count the number of R waves over 6 seconds and multiply by ten).
P waves: Check to see whether P waves are present before each QRS complex, that each P
wave looks similar in size and shape, and the waveform is upright (positive deflection) in Lead
II. The P waves should also maintain a consistent appearance.
P-R interval: The normal interval is between 0.12 and 0.2 seconds, and is constant.
QRS complexes: All complexes look similar and are predominantly positive. Each QRS
complex should be no more than 0.1 seconds wide (some texts state 0.12 seconds).
Classifying the rhythm
Rhythms can be generally classified under the following categories:
Sinus Rhythm Rate P wave P-R interval QRS complex
Sinus rhythm Essentially regular 60-100 Normal, precede 0.12-0.20 & Normal (0.10 or
each QRS constant less)
Sinus Regularly irregular 60-100 Normal, precede 0.12-0.20 & Normal (0.10 or
dysrhythmia each QRS constant less)
Sinus Essentially regular < 60 Normal, precede 0.12-0.20 & Normal (0.10 or
bradycardia each QRS constant less)
Sinus Essentially regular > 100 - Normal, precede 0.12-0.20 & Normal (0.10 or
Tachycardia 180 each QRS usually less)
constant
Sinoatrial Exit Irregular when Normal, precede 0.12-0.20 & Normal (0.10 or
Block block is present each QRS usually less)
QRS pause IS 60-100 No P wave when constant May be wide if
multiple of P-P block occurs a conduction
interval defect exists
Sinus Arrest Irregular due to the Normal, precede 0.12-0.20 & Normal (0.10 or
pause each QRS usually less)
QRS pause is NOT 60-100 No P wave when constant May be wide if
multiple of P-P arrest occurs a conduction
interval defect exists
Atrial Rhythm Rate P wave P-R interval QRS complex
Supraventricular Essentially regular 160- Present or 0.12-0.20 if Usually normal
tachycardia 240 absent. May be pacemaker is in (0.10 or less)
up-right or the atria, or less
(Atrial inverted than 0.12 if
Tachycardia) depending on pace site is
the origin. lower. May
also occur after
the QRS.
Atrial flutter Usually regular Atrial Not seen (F N/A Usually normal
rate av. waves are saw- (0.10 or less)
300 toothed)
V rate
av. 150
This study source was downloaded by 100000851739762 from CourseHero.com on 09-09-2022 05:01:35 GMT -05:00
https://www.coursehero.com/file/23492163/Dysrhythmia-interpretation/
