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t o r e g . c o m
Dr. Mete ALPASLAN
Intermittent Wolff-Parkinson-White (WPW) Syndrome
WPW syndrome may be
intermittent
In some patients, preexcitation may be seen on occasional days.
In some others, preexcitation may appear in a few beats and then disappear and reappear again.
In patients with complete AV block, some P waves buried in QRS complex, will deform the QRS and may erroneously give the impression of delta wave and therefore intermittent WPW syndrome, at first glance.
How to differentiate intermittent preecitation from fusion beat?
The fusion beat occurs due to fortuitous meeting of a supraventricular impulse and ventricular impulse in the ventricle.
This fortuitous meeting of impulses result in QRS complexes with different shapes.
On the other hand, intermittent preexcitation results in similar QRS complexes with delta waves.
ECG 1. Intermittent WPW syndrome. Only some beats show short PR interval and delta waves while others do not.
Dr. Beatrice Brembilla has donated the above ECG to our website.
Click here for a more detailed ECG
ECG 2. WPW syndrome in an 11 years old child. Preexcitation was not observed everyday. Electrophysiological study revealed
inferior accessory pathyway and the child underwent successfull radiofrequency ablation. This ECG also shows sinus
arrhythmia.
Dr. Christian Balmer has donated the above ECG to our website.
Click here for a more detailed ECG
ECG 3. Intermittent WPW syndrome in child. .
Dr. Christopher Rausch has donated the above ECG to our website.
Click here for a more detailed ECG
ECG 4. The left side of above ECG shows complete AV block. P waves are not related to QRS complexes.
Some P waves, buried in the QRS, deform the QRS complex and give the impression of intermittent WPW syndrome at first glance
The right side shows Wenkebach AV block.
PR interval gradually prolongs; 3rd and 6th P waves are dropped (not conducted to the ventricles).
Click here for a more detailed ECG
ECG 5. The ECG above belongs to a 68 years-old woman.
Only some of the beats show short PR interval and delta wave (preexcitation) (denoting intermittent WPW).
At first glance, these two beats may seem like fusion beats.
Especially, if there was only one of them, it would be more easy to misdiagnose it as a fusion beat.
However, the fusion beat arises due to fortuitous meeting of a supraventricular impulse and ventricular impulse in the ventricle.
Therefore it is almost impossible to see fusion beats with similar morphology.
On the other hand, the ECG above shows two beats with similar delta waves, suggesting intermittent preexcitation.
Dr. Sinan Altan Kocaman has donated the above ECG to our website.
Click here for a more detailed ECG
ECG 6a. The ECG above belongs to a 30 years-old patient with palpitation.
All beats show short PR interval with delta waves (preexcitation).
Dr. Daniel Opazo D. has donated the above ECG to our website.
ECG 6b. The ECG above belongs to the same patient. It was recorded 15 minutes after the ECG 6a.
Only some beats show short PR interval with delta waves (intermittent preexcitation).
Preexcitation affects not only QRS duration but also QRS amplitude and T wave shape.
Dr. Daniel Opazo D. has donated the above ECG to our website.
ECG 6c. The ECG above belongs to the same patient. It was recorded 15 minutes after the ECG 6b.
No beats show short PR interval with delta waves (no preexcitation).
Dr. Daniel Opazo D. has donated the above ECG to our website.
In some patients, preexcitation may be seen on occasional days.
In some others, preexcitation may appear in a few beats and then disappear and reappear again.
In patients with complete AV block, some P waves buried in QRS complex, will deform the QRS and may erroneously give the impression of delta wave and therefore intermittent WPW syndrome, at first glance.
How to differentiate intermittent preecitation from fusion beat?
The fusion beat occurs due to fortuitous meeting of a supraventricular impulse and ventricular impulse in the ventricle.
This fortuitous meeting of impulses result in QRS complexes with different shapes.
On the other hand, intermittent preexcitation results in similar QRS complexes with delta waves.
ECG 1. Intermittent WPW syndrome. Only some beats show short PR interval and delta waves while others do not.
Dr. Beatrice Brembilla has donated the above ECG to our website.
Click here for a more detailed ECG
ECG 2. WPW syndrome in an 11 years old child. Preexcitation was not observed everyday. Electrophysiological study revealed
inferior accessory pathyway and the child underwent successfull radiofrequency ablation. This ECG also shows sinus
arrhythmia.
Dr. Christian Balmer has donated the above ECG to our website.
Click here for a more detailed ECG
ECG 3. Intermittent WPW syndrome in child. .
Dr. Christopher Rausch has donated the above ECG to our website.
Click here for a more detailed ECG
ECG 4. The left side of above ECG shows complete AV block. P waves are not related to QRS complexes.
Some P waves, buried in the QRS, deform the QRS complex and give the impression of intermittent WPW syndrome at first glance
The right side shows Wenkebach AV block.
PR interval gradually prolongs; 3rd and 6th P waves are dropped (not conducted to the ventricles).
Click here for a more detailed ECG
ECG 5. The ECG above belongs to a 68 years-old woman.
Only some of the beats show short PR interval and delta wave (preexcitation) (denoting intermittent WPW).
At first glance, these two beats may seem like fusion beats.
Especially, if there was only one of them, it would be more easy to misdiagnose it as a fusion beat.
However, the fusion beat arises due to fortuitous meeting of a supraventricular impulse and ventricular impulse in the ventricle.
Therefore it is almost impossible to see fusion beats with similar morphology.
On the other hand, the ECG above shows two beats with similar delta waves, suggesting intermittent preexcitation.
Dr. Sinan Altan Kocaman has donated the above ECG to our website.
Click here for a more detailed ECG
ECG 6a. The ECG above belongs to a 30 years-old patient with palpitation.
All beats show short PR interval with delta waves (preexcitation).
Dr. Daniel Opazo D. has donated the above ECG to our website.
ECG 6b. The ECG above belongs to the same patient. It was recorded 15 minutes after the ECG 6a.
Only some beats show short PR interval with delta waves (intermittent preexcitation).
Preexcitation affects not only QRS duration but also QRS amplitude and T wave shape.
Dr. Daniel Opazo D. has donated the above ECG to our website.
ECG 6c. The ECG above belongs to the same patient. It was recorded 15 minutes after the ECG 6b.
No beats show short PR interval with delta waves (no preexcitation).
Dr. Daniel Opazo D. has donated the above ECG to our website.