Diagnostic criteria

  Atria and ventricles depolarize independently:

            - P waves are regular in themselves and QRS waves are regular among themselves.

            - Every P wave is not followed by a QRS complex.

            - Some QRS complexes may accidentally have preceeding P waves,

            - Some QRS complexes may have P waves buried in them.

            - Some P waves, buried in the QRS, will deform the QRS complex and

              may falsely give the impression of
delta wave and therefore intermittent WPW syndrome

              at first glance.

  If the escape rhythm is
junctional, then heart rate is 40-60/minute with narrow QRS complexes.

  If the escape rhythm is
idioventricular, then heart rate is 20-40/minute with wide QRS complexes.

 
Equalization of R-R intervals in a patient with atrial fibrillation suggests

      development of
complete AV block.

  In patients with atrial fibrillation who are already under Digoxin therapy,

     
equalization of R-R intervals suggests development of complete AV block due to Digoxin intoxication.

  Rarely, complete AV block may be
congenital.





ECG 1. Third degree (complete) AV block in a 68 years-old woman with Systemic Sclerosis (Scleroderma).
Multidetector CT coronary angiography showed normal coronary arteries.

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The ECG above has been used with the permission of Anatolian Journal of Cardiology and AVES Publishing.

Click here to see the related article of Dr. Canpolat et al.





ECG 2. Third degree (complete) AV block.
P waves are completely unrelated to the QRS complexes.


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ECG 3. The rhythm strip at the bottom of the above tracing shows complete AV block on the left (
P waves are not related to
QRS complexes
) which is then followed by 2:1 AV block ( only 1 of every two P waves is conducted ).


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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).

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ECG 5. The ECG above belongs to a 58 years-old man who admitted lately to the hospital and was diagnosed as
inferior myocardial infarction.
Q waves , ST segment elevation and negative T waves are seen in inferior leads.
Also,
the P waves are not related to the QRS complexes : complete AV block .

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ECG 6. The ECG above belongs to a 55 years-old woman who developed persistent av block (A) after consumption of
Grayanotoxin-containing mad honey. The ECG on the right (B) was recorded after implantation of a permanent pacemaker.
Coronary angiography showed normal coronary arteries.

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The ECG above has been used with the permission of Anatolian Journal of Cardiology and AVES Publishing.

Click here to read the relevant article of Dr. Canpolat et al.






ECG 7. Complete AV block during acute myocardial infarction.

P waves
are not related to QRS complexes.

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ECG 8. The ECG above shows complete AV block. P waves are not related to the QRS complexes,
At times, P waves are seen in front or at the end of the QRS complexes and distort them.

Pediatric cardiologist Prof. Dr. Birgul Varan has donated the above ECG to our website.

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ECG 9a. The ECG above is from a 6 months-old baby with congenital complete AV block.
P waves are not related to the QRS complexes. Therefore, some P waves are buried in the QRS complexes.
P wave rate is normal for a baby; not to be confused with atrial flutter or atrial tachycardia.

Pediatric cardiologist Dr. Mahmut Gokdemir has donated the above ECG to our website.

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ECG 9b. Rhythm tracing from the same baby: complete AV block is seen. P waves are not related to the QRS complexes.
P wave rate is normal for a baby; not to be confused with atrial flutter or atrial tachycardia.

Pediatric cardiologist Dr. Mahmut Gokdemir has donated the above ECG to our website.

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ECG 10a. The above ECG shows both complete AV block and interatrial block.
It was recorded during
acute inferior wall myocardial infarction.
P waves are not related to the QRS complexes. Therefore, some P waves are buried in QRS complexes.
The P wave width is slightly more than 120 milliseconds: interatrial block.
This ECG was recorded at a calibration of
20 mm/mV to show interatrial block.

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ECG 10b. Above is his ECG at a
standard 10 mm/mV calibration.
It is difficult to see interatrial block and complete AV block, at first glance.

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ECG 11a. The ECG above is from a 95 years-old woman with atrial fibrillation and complete av block.
Although atrial fibrillation is known as an "irregularly irregular rhythm", it becomes a regular rhythm
when complete av block developes. RR intervals are regular in the above ECG.
The above ECG is recorded at a standard calibration of 10mm/mV and the fibrillatory waves are hardly noticeable.

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ECG 11b. The above ECG belongs to the same patient.
It is recorded at a calibration of 20 mm/mV.
Now, it is more easy to see the fibrillatory waves.
The RR intervals are equal (regular) due to complete AV block.

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