Telemetry monitoring is one of the
most exciting and challenging facets of caring for a cardiac patient.
There are so many rhythms and some of them try to fool us, by looking so much like
others!!! With some study, and a little practice and patience, you can master
this exciting rhelm of Cardiac nursing! Whether you are wanting to work on a
Telemetry unit, or if you are going to ER or ICU/CCU, you can find some help
in your quest HERE!!
For those of you who are wanting to do Telemetry,
as you look at the strips, focus your attention on the ones that are single lead
strips, or in the multiple strips, focus on the "ekg" readings...but if you are
planning on ER or ICU/CCU, then check out the other readings as well. This is also a
good introduction to my CARDIAC HEMODYNAMICS page!
What does one heartbeat look like on Telemetry???
The above is what one simple heartbeat looks like on a telemetry strip.
The P wave shows the atria contracting
The QRS shows the ventricles contracting
The T wave shows the ventricles relaxing
NORMAL SINUS RHYTHM
a normal EKG with P, QRS and T waves present
a PR interval of 0.12 - 0.20 seconds
a regular interval between each QRS complex (R-R interval) of 0.60 - 1.00 seconds
a distinct a wave in the CVP trace due to atrial contraction
a regular arterial pulse pressure (difference between systolic and diastolic pressures)
there may be minor regular variation in heart rate and pulse pressure associated with
respiration (sinus arrhythmia)
SINUS BRADYCARDIA
Sinus bradycardia is a a sinus rhythm (originates in the SA node) which is slower than 60
beats per minute (BPM). Sinus bradycardia may occur with vagal (parasympathetic)
stimulation, such as in trained athletes or in patients with the carotid sinus syndrome (in whom
baroreceptors are overly sensitive to pressure, resulting in excessive vagal stimulation). Sinus
bradycardia may also occur as a result of pharmacological beta-blockade.
The rhythm is similar to normal sinus rhythm, except that the R-R interval is longer than one second.
The pulse pressure may be higher due to a greater stroke volume (resulting in greater systolic
pressure) and increased time for diastolic run-off (resulting in lower diastolic pressure)
SINUS TACHYCARDIA
Sinus tachycardia refers to a sinus rhythm with a heart rate greater than 100 BPM.
Sinus tachycardia may be due to fever, which results in increased excitability of the SA node.
Sympathetic stimulation (from a variety of causes, including medications) and cardiac toxicity may also cause sinus
tachycardia.
The rhythm is similar to normal sinus rhythm, except that the R-R interval is shorter than 0.6 seconds.
The a wave may tend to merge with the v wave in the CVP trace, and you may not be able to distinguish the P wave.
The pulse pressure may be lower due to a
lower stroke volume and decreased time for diastolic run-off.
ATRIAL FLUTTER
Notice in the above ECG that the flutter waves are larger than P waves and they are
characteristically saw-toothed in form. This is a consequence of circular depolarisation of the atria,
which also results in largely ineffectual atrial pumping, since parts of the atria are relaxing while other
parts are contracting. Consequently, reduced cardiac output is a significant consequence of atrial
flutter.
Notice also that not every flutter wave results in a QRS complex (ventricular depolarisation) since
some of the flutter waves reach the AV node when it is refractory (insufficiently repolarised to
conduct an action potential). There will generally be a fixed ratio of flutter waves to QRS complexes,
such as 2:1, 3:1 or 4:1, though this ratio may alter in a regular or an irregular way.
In this example there is 2:1 and 3:1 conduction. Notice also a waves in the CVP trace
corresponding to the flutter waves.
Key features of atrial flutter:
saw-tooth-shaped flutter waves in the ECG
atrial rate typically 200-350
whole number ratio of flutter waves to QRS complexes
ATRIAL FIBRILLATION
ATRIOVENTRICULAR CONDUCTION BLOCKS
FIRST DEGREE BLOCK
SECOND DEGREE BLOCK
THIRD DEGREE BLOCK
Once the ventricles pick up a rhythm (usually from some part of the Purkinje system) it is totally
dissociated and asynchronous from the atrial rhythm.
first degree block - prolonged PR interval
second degree block - not all impulses conducted through the AV junction
third degree block - no impulses conducted through AV junction, dissociated atrial and
ventricular rhythms
JUNCTIONAL RHYTHM
A feature of junctional rhythms is the variable PR interval, dependent on the location of the
pacemaker within the AV junction. The PR interval will generally be less than normal. In the above
example the PR interval is close to zero, and the P wave is obscured by the QRS complex.
If the PR interval is so short that the atria contract at the same time as the ventricles then a large a
wave results (a cannon wave), as can be seen in the above diagram. This occurs because the atria
cannot eject into the ventricles and so develop a higher pressure. A consequence of this is reduced
ventricular filling and hence reduced cardiac output.
In the case of a junctional rhythm the His-Purkinje system conducts in the normal fashion, so the
QRS complex will usually be normal.
In the above diagram the rhythm changes from junctional to sinus. Note the appearance of the P
wave, the increased arterial pressure (due to increased ventricular filling upon effective atrial
pumping) and the loss of cannon waves in the CVP trace, with the return of normal a and v waves.
Key features of junctional rhythm:
(often) decreased PR interval which can result in
P waves obscured by QRS complexes(thus, they can't be seen) cannon waves in CVP and PAWP traces
reduced cardiac output
normal QRS complexes
regular RR interval
Oh No No!!! You're not done yet!!! Click on Timone, the Telemetry YAK to go to the next page of rythm strips!!!!
For those of you who are wanting to do Telemetry,
as you look at the strips, focus your attention on the ones that are single lead
strips, or in the multiple strips, focus on the "ekg" readings...but if you are
planning on ER or ICU/CCU, then check out the other readings as well. This is also a
good introduction to my CARDIAC HEMODYNAMICS page!
What does one heartbeat look like on Telemetry???
The above is what one simple heartbeat looks like on a telemetry strip.
The P wave shows the atria contracting
The QRS shows the ventricles contracting
The T wave shows the ventricles relaxing
NORMAL SINUS RHYTHM
a normal EKG with P, QRS and T waves present
a PR interval of 0.12 - 0.20 seconds
a regular interval between each QRS complex (R-R interval) of 0.60 - 1.00 seconds
a distinct a wave in the CVP trace due to atrial contraction
a regular arterial pulse pressure (difference between systolic and diastolic pressures)
there may be minor regular variation in heart rate and pulse pressure associated with
respiration (sinus arrhythmia)
SINUS BRADYCARDIA
Sinus bradycardia is a a sinus rhythm (originates in the SA node) which is slower than 60
beats per minute (BPM). Sinus bradycardia may occur with vagal (parasympathetic)
stimulation, such as in trained athletes or in patients with the carotid sinus syndrome (in whom
baroreceptors are overly sensitive to pressure, resulting in excessive vagal stimulation). Sinus
bradycardia may also occur as a result of pharmacological beta-blockade.
The rhythm is similar to normal sinus rhythm, except that the R-R interval is longer than one second.
The pulse pressure may be higher due to a greater stroke volume (resulting in greater systolic
pressure) and increased time for diastolic run-off (resulting in lower diastolic pressure)
SINUS TACHYCARDIA
Sinus tachycardia refers to a sinus rhythm with a heart rate greater than 100 BPM.
Sinus tachycardia may be due to fever, which results in increased excitability of the SA node.
Sympathetic stimulation (from a variety of causes, including medications) and cardiac toxicity may also cause sinus
tachycardia.
The rhythm is similar to normal sinus rhythm, except that the R-R interval is shorter than 0.6 seconds.
The a wave may tend to merge with the v wave in the CVP trace, and you may not be able to distinguish the P wave.
The pulse pressure may be lower due to a
lower stroke volume and decreased time for diastolic run-off.
ATRIAL FLUTTER
Notice in the above ECG that the flutter waves are larger than P waves and they are
characteristically saw-toothed in form. This is a consequence of circular depolarisation of the atria,
which also results in largely ineffectual atrial pumping, since parts of the atria are relaxing while other
parts are contracting. Consequently, reduced cardiac output is a significant consequence of atrial
flutter.
Notice also that not every flutter wave results in a QRS complex (ventricular depolarisation) since
some of the flutter waves reach the AV node when it is refractory (insufficiently repolarised to
conduct an action potential). There will generally be a fixed ratio of flutter waves to QRS complexes,
such as 2:1, 3:1 or 4:1, though this ratio may alter in a regular or an irregular way.
In this example there is 2:1 and 3:1 conduction. Notice also a waves in the CVP trace
corresponding to the flutter waves.
Key features of atrial flutter:
saw-tooth-shaped flutter waves in the ECG
atrial rate typically 200-350
whole number ratio of flutter waves to QRS complexes
ATRIAL FIBRILLATION
ATRIOVENTRICULAR CONDUCTION BLOCKS
FIRST DEGREE BLOCK
SECOND DEGREE BLOCK
THIRD DEGREE BLOCK
Once the ventricles pick up a rhythm (usually from some part of the Purkinje system) it is totally
dissociated and asynchronous from the atrial rhythm.
first degree block - prolonged PR interval
second degree block - not all impulses conducted through the AV junction
third degree block - no impulses conducted through AV junction, dissociated atrial and
ventricular rhythms
JUNCTIONAL RHYTHM
A feature of junctional rhythms is the variable PR interval, dependent on the location of the
pacemaker within the AV junction. The PR interval will generally be less than normal. In the above
example the PR interval is close to zero, and the P wave is obscured by the QRS complex.
If the PR interval is so short that the atria contract at the same time as the ventricles then a large a
wave results (a cannon wave), as can be seen in the above diagram. This occurs because the atria
cannot eject into the ventricles and so develop a higher pressure. A consequence of this is reduced
ventricular filling and hence reduced cardiac output.
In the case of a junctional rhythm the His-Purkinje system conducts in the normal fashion, so the
QRS complex will usually be normal.
In the above diagram the rhythm changes from junctional to sinus. Note the appearance of the P
wave, the increased arterial pressure (due to increased ventricular filling upon effective atrial
pumping) and the loss of cannon waves in the CVP trace, with the return of normal a and v waves.
Key features of junctional rhythm:
(often) decreased PR interval which can result in
P waves obscured by QRS complexes(thus, they can't be seen) cannon waves in CVP and PAWP traces
reduced cardiac output
normal QRS complexes
regular RR interval
Oh No No!!! You're not done yet!!! Click on Timone, the Telemetry YAK to go to the next page of rythm strips!!!!
What does one heartbeat look like on Telemetry???
The above is what one simple heartbeat looks like on a telemetry strip.
The P wave shows the atria contracting
The QRS shows the ventricles contracting
The T wave shows the ventricles relaxing
NORMAL SINUS RHYTHM
a normal EKG with P, QRS and T waves present
a PR interval of 0.12 - 0.20 seconds
a regular interval between each QRS complex (R-R interval) of 0.60 - 1.00 seconds
a distinct a wave in the CVP trace due to atrial contraction
a regular arterial pulse pressure (difference between systolic and diastolic pressures)
there may be minor regular variation in heart rate and pulse pressure associated with
respiration (sinus arrhythmia)
SINUS BRADYCARDIA
Sinus bradycardia is a a sinus rhythm (originates in the SA node) which is slower than 60
beats per minute (BPM). Sinus bradycardia may occur with vagal (parasympathetic)
stimulation, such as in trained athletes or in patients with the carotid sinus syndrome (in whom
baroreceptors are overly sensitive to pressure, resulting in excessive vagal stimulation). Sinus
bradycardia may also occur as a result of pharmacological beta-blockade.
The rhythm is similar to normal sinus rhythm, except that the R-R interval is longer than one second.
The pulse pressure may be higher due to a greater stroke volume (resulting in greater systolic
pressure) and increased time for diastolic run-off (resulting in lower diastolic pressure)
SINUS TACHYCARDIA
Sinus tachycardia refers to a sinus rhythm with a heart rate greater than 100 BPM.
Sinus tachycardia may be due to fever, which results in increased excitability of the SA node.
Sympathetic stimulation (from a variety of causes, including medications) and cardiac toxicity may also cause sinus
tachycardia.
The rhythm is similar to normal sinus rhythm, except that the R-R interval is shorter than 0.6 seconds.
The a wave may tend to merge with the v wave in the CVP trace, and you may not be able to distinguish the P wave.
The pulse pressure may be lower due to a
lower stroke volume and decreased time for diastolic run-off.
ATRIAL FLUTTER
Notice in the above ECG that the flutter waves are larger than P waves and they are
characteristically saw-toothed in form. This is a consequence of circular depolarisation of the atria,
which also results in largely ineffectual atrial pumping, since parts of the atria are relaxing while other
parts are contracting. Consequently, reduced cardiac output is a significant consequence of atrial
flutter.
Notice also that not every flutter wave results in a QRS complex (ventricular depolarisation) since
some of the flutter waves reach the AV node when it is refractory (insufficiently repolarised to
conduct an action potential). There will generally be a fixed ratio of flutter waves to QRS complexes,
such as 2:1, 3:1 or 4:1, though this ratio may alter in a regular or an irregular way.
In this example there is 2:1 and 3:1 conduction. Notice also a waves in the CVP trace
corresponding to the flutter waves.
Key features of atrial flutter:
saw-tooth-shaped flutter waves in the ECG
atrial rate typically 200-350
whole number ratio of flutter waves to QRS complexes
ATRIAL FIBRILLATION
ATRIOVENTRICULAR CONDUCTION BLOCKS
FIRST DEGREE BLOCK
SECOND DEGREE BLOCK
THIRD DEGREE BLOCK
Once the ventricles pick up a rhythm (usually from some part of the Purkinje system) it is totally
dissociated and asynchronous from the atrial rhythm.
first degree block - prolonged PR interval
second degree block - not all impulses conducted through the AV junction
third degree block - no impulses conducted through AV junction, dissociated atrial and
ventricular rhythms
JUNCTIONAL RHYTHM
A feature of junctional rhythms is the variable PR interval, dependent on the location of the
pacemaker within the AV junction. The PR interval will generally be less than normal. In the above
example the PR interval is close to zero, and the P wave is obscured by the QRS complex.
If the PR interval is so short that the atria contract at the same time as the ventricles then a large a
wave results (a cannon wave), as can be seen in the above diagram. This occurs because the atria
cannot eject into the ventricles and so develop a higher pressure. A consequence of this is reduced
ventricular filling and hence reduced cardiac output.
In the case of a junctional rhythm the His-Purkinje system conducts in the normal fashion, so the
QRS complex will usually be normal.
In the above diagram the rhythm changes from junctional to sinus. Note the appearance of the P
wave, the increased arterial pressure (due to increased ventricular filling upon effective atrial
pumping) and the loss of cannon waves in the CVP trace, with the return of normal a and v waves.
Key features of junctional rhythm:
(often) decreased PR interval which can result in
P waves obscured by QRS complexes(thus, they can't be seen) cannon waves in CVP and PAWP traces
reduced cardiac output
normal QRS complexes
regular RR interval
Oh No No!!! You're not done yet!!! Click on Timone, the Telemetry YAK to go to the next page of rythm strips!!!!
|
The P wave shows the atria contracting |
|
The QRS shows the ventricles contracting |
|
The T wave shows the ventricles relaxing |
NORMAL SINUS RHYTHM
|
a normal EKG with P, QRS and T waves present |
|
a PR interval of 0.12 - 0.20 seconds |
|
a regular interval between each QRS complex (R-R interval) of 0.60 - 1.00 seconds |
|
a distinct a wave in the CVP trace due to atrial contraction |
|
a regular arterial pulse pressure (difference between systolic and diastolic pressures) |
|
there may be minor regular variation in heart rate and pulse pressure associated with respiration (sinus arrhythmia) |
SINUS BRADYCARDIA
Sinus bradycardia is a a sinus rhythm (originates in the SA node) which is slower than 60
beats per minute (BPM). Sinus bradycardia may occur with vagal (parasympathetic)
stimulation, such as in trained athletes or in patients with the carotid sinus syndrome (in whom
baroreceptors are overly sensitive to pressure, resulting in excessive vagal stimulation). Sinus
bradycardia may also occur as a result of pharmacological beta-blockade.
The rhythm is similar to normal sinus rhythm, except that the R-R interval is longer than one second.
The pulse pressure may be higher due to a greater stroke volume (resulting in greater systolic
pressure) and increased time for diastolic run-off (resulting in lower diastolic pressure)
SINUS TACHYCARDIA
Sinus tachycardia refers to a sinus rhythm with a heart rate greater than 100 BPM.
Sinus tachycardia may be due to fever, which results in increased excitability of the SA node.
Sympathetic stimulation (from a variety of causes, including medications) and cardiac toxicity may also cause sinus
tachycardia.
The rhythm is similar to normal sinus rhythm, except that the R-R interval is shorter than 0.6 seconds.
The a wave may tend to merge with the v wave in the CVP trace, and you may not be able to distinguish the P wave.
The pulse pressure may be lower due to a
lower stroke volume and decreased time for diastolic run-off.
ATRIAL FLUTTER
Notice in the above ECG that the flutter waves are larger than P waves and they are
characteristically saw-toothed in form. This is a consequence of circular depolarisation of the atria,
which also results in largely ineffectual atrial pumping, since parts of the atria are relaxing while other
parts are contracting. Consequently, reduced cardiac output is a significant consequence of atrial
flutter.
Notice also that not every flutter wave results in a QRS complex (ventricular depolarisation) since
some of the flutter waves reach the AV node when it is refractory (insufficiently repolarised to
conduct an action potential). There will generally be a fixed ratio of flutter waves to QRS complexes,
such as 2:1, 3:1 or 4:1, though this ratio may alter in a regular or an irregular way.
In this example there is 2:1 and 3:1 conduction. Notice also a waves in the CVP trace
corresponding to the flutter waves.
Key features of atrial flutter:
saw-tooth-shaped flutter waves in the ECG
atrial rate typically 200-350
whole number ratio of flutter waves to QRS complexes
ATRIAL FIBRILLATION
ATRIOVENTRICULAR CONDUCTION BLOCKS
FIRST DEGREE BLOCK
SECOND DEGREE BLOCK
THIRD DEGREE BLOCK
Once the ventricles pick up a rhythm (usually from some part of the Purkinje system) it is totally
dissociated and asynchronous from the atrial rhythm.
first degree block - prolonged PR interval
second degree block - not all impulses conducted through the AV junction
third degree block - no impulses conducted through AV junction, dissociated atrial and
ventricular rhythms
JUNCTIONAL RHYTHM
A feature of junctional rhythms is the variable PR interval, dependent on the location of the
pacemaker within the AV junction. The PR interval will generally be less than normal. In the above
example the PR interval is close to zero, and the P wave is obscured by the QRS complex.
If the PR interval is so short that the atria contract at the same time as the ventricles then a large a
wave results (a cannon wave), as can be seen in the above diagram. This occurs because the atria
cannot eject into the ventricles and so develop a higher pressure. A consequence of this is reduced
ventricular filling and hence reduced cardiac output.
In the case of a junctional rhythm the His-Purkinje system conducts in the normal fashion, so the
QRS complex will usually be normal.
In the above diagram the rhythm changes from junctional to sinus. Note the appearance of the P
wave, the increased arterial pressure (due to increased ventricular filling upon effective atrial
pumping) and the loss of cannon waves in the CVP trace, with the return of normal a and v waves.
Key features of junctional rhythm:
(often) decreased PR interval which can result in
P waves obscured by QRS complexes(thus, they can't be seen) cannon waves in CVP and PAWP traces
reduced cardiac output
normal QRS complexes
regular RR interval
Oh No No!!! You're not done yet!!! Click on Timone, the Telemetry YAK to go to the next page of rythm strips!!!!
SINUS TACHYCARDIA
Sinus tachycardia refers to a sinus rhythm with a heart rate greater than 100 BPM.
Sinus tachycardia may be due to fever, which results in increased excitability of the SA node.
Sympathetic stimulation (from a variety of causes, including medications) and cardiac toxicity may also cause sinus
tachycardia.
The rhythm is similar to normal sinus rhythm, except that the R-R interval is shorter than 0.6 seconds.
The a wave may tend to merge with the v wave in the CVP trace, and you may not be able to distinguish the P wave.
The pulse pressure may be lower due to a
lower stroke volume and decreased time for diastolic run-off.
ATRIAL FLUTTER
Notice in the above ECG that the flutter waves are larger than P waves and they are
characteristically saw-toothed in form. This is a consequence of circular depolarisation of the atria,
which also results in largely ineffectual atrial pumping, since parts of the atria are relaxing while other
parts are contracting. Consequently, reduced cardiac output is a significant consequence of atrial
flutter.
Notice also that not every flutter wave results in a QRS complex (ventricular depolarisation) since
some of the flutter waves reach the AV node when it is refractory (insufficiently repolarised to
conduct an action potential). There will generally be a fixed ratio of flutter waves to QRS complexes,
such as 2:1, 3:1 or 4:1, though this ratio may alter in a regular or an irregular way.
In this example there is 2:1 and 3:1 conduction. Notice also a waves in the CVP trace
corresponding to the flutter waves.
Key features of atrial flutter:
saw-tooth-shaped flutter waves in the ECG
atrial rate typically 200-350
whole number ratio of flutter waves to QRS complexes
ATRIAL FIBRILLATION
ATRIOVENTRICULAR CONDUCTION BLOCKS
FIRST DEGREE BLOCK
SECOND DEGREE BLOCK
THIRD DEGREE BLOCK
Once the ventricles pick up a rhythm (usually from some part of the Purkinje system) it is totally
dissociated and asynchronous from the atrial rhythm.
first degree block - prolonged PR interval
second degree block - not all impulses conducted through the AV junction
third degree block - no impulses conducted through AV junction, dissociated atrial and
ventricular rhythms
JUNCTIONAL RHYTHM
A feature of junctional rhythms is the variable PR interval, dependent on the location of the
pacemaker within the AV junction. The PR interval will generally be less than normal. In the above
example the PR interval is close to zero, and the P wave is obscured by the QRS complex.
If the PR interval is so short that the atria contract at the same time as the ventricles then a large a
wave results (a cannon wave), as can be seen in the above diagram. This occurs because the atria
cannot eject into the ventricles and so develop a higher pressure. A consequence of this is reduced
ventricular filling and hence reduced cardiac output.
In the case of a junctional rhythm the His-Purkinje system conducts in the normal fashion, so the
QRS complex will usually be normal.
In the above diagram the rhythm changes from junctional to sinus. Note the appearance of the P
wave, the increased arterial pressure (due to increased ventricular filling upon effective atrial
pumping) and the loss of cannon waves in the CVP trace, with the return of normal a and v waves.
Key features of junctional rhythm:
(often) decreased PR interval which can result in
P waves obscured by QRS complexes(thus, they can't be seen) cannon waves in CVP and PAWP traces
reduced cardiac output
normal QRS complexes
regular RR interval
Oh No No!!! You're not done yet!!! Click on Timone, the Telemetry YAK to go to the next page of rythm strips!!!!
ATRIAL FLUTTER
Notice in the above ECG that the flutter waves are larger than P waves and they are characteristically saw-toothed in form. This is a consequence of circular depolarisation of the atria, which also results in largely ineffectual atrial pumping, since parts of the atria are relaxing while other parts are contracting. Consequently, reduced cardiac output is a significant consequence of atrial flutter.
Notice also that not every flutter wave results in a QRS complex (ventricular depolarisation) since some of the flutter waves reach the AV node when it is refractory (insufficiently repolarised to conduct an action potential). There will generally be a fixed ratio of flutter waves to QRS complexes, such as 2:1, 3:1 or 4:1, though this ratio may alter in a regular or an irregular way. In this example there is 2:1 and 3:1 conduction. Notice also a waves in the CVP trace corresponding to the flutter waves.
Key features of atrial flutter:
|
saw-tooth-shaped flutter waves in the ECG |
|
atrial rate typically 200-350 |
|
whole number ratio of flutter waves to QRS complexes |
ATRIAL FIBRILLATION
ATRIOVENTRICULAR CONDUCTION BLOCKS
FIRST DEGREE BLOCK
SECOND DEGREE BLOCK
THIRD DEGREE BLOCK
Once the ventricles pick up a rhythm (usually from some part of the Purkinje system) it is totally dissociated and asynchronous from the atrial rhythm.
|
first degree block - prolonged PR interval |
|
second degree block - not all impulses conducted through the AV junction |
|
third degree block - no impulses conducted through AV junction, dissociated atrial and ventricular rhythms |
JUNCTIONAL RHYTHM
A feature of junctional rhythms is the variable PR interval, dependent on the location of the pacemaker within the AV junction. The PR interval will generally be less than normal. In the above example the PR interval is close to zero, and the P wave is obscured by the QRS complex.
If the PR interval is so short that the atria contract at the same time as the ventricles then a large a wave results (a cannon wave), as can be seen in the above diagram. This occurs because the atria cannot eject into the ventricles and so develop a higher pressure. A consequence of this is reduced ventricular filling and hence reduced cardiac output.
In the case of a junctional rhythm the His-Purkinje system conducts in the normal fashion, so the QRS complex will usually be normal.
In the above diagram the rhythm changes from junctional to sinus. Note the appearance of the P wave, the increased arterial pressure (due to increased ventricular filling upon effective atrial pumping) and the loss of cannon waves in the CVP trace, with the return of normal a and v waves.
Key features of junctional rhythm:
|
(often) decreased PR interval which can result in P waves obscured by QRS complexes(thus, they can't be seen) cannon waves in CVP and PAWP traces reduced cardiac output |
|
normal QRS complexes |
|
regular RR interval |