1. Volume 13, Issue 1, Pages 321-323 (January 2016)
Atrial tachycardia with Wenckebach atrioventricular conduction mechanism: What is the origin of the beat following the pause? 
Vincenzo Carbone, MD, Maria Pia Calabrò, MD, Vincenzo Marafioti, MD, Giuseppe Oreto, MD 
Heart Rhythm 
Volume 13, Issue 1, Pages (January 2016)
DOI: /j.hrthm
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2. Figure 1
Continuous ECG recording strips of lead V1. Numbers below the tracing indicate the duration of the pauses (in milliseconds).
Heart Rhythm  , DOI: ( /j.hrthm )
Copyright © 2015 Heart Rhythm Society Terms and Conditions

3. Figure 2
Enlargement of the bottom strip of Figure 1 showing P-R and R-R intervals (in milliseconds). The P waves of tachycardia are labeled with dots. A Wenckebach AV nodal conduction is seen, ending in pauses of variable length. The beats following the pauses are clearly dissociated from the coincidental P waves, as demonstrated by the nearly virtual P-to-R intervals. See text for discussion.
Heart Rhythm  , DOI: ( /j.hrthm )
Copyright © 2015 Heart Rhythm Society Terms and Conditions

4. Figure 3
Ladder diagram illustrating the mechanism of conduction. Solid lines indicate conduction over the fast nodal pathway. Broken lines indicate conduction over the slow nodal pathway. Horizontal bars represent the refractory period of the fast pathway. The QRS complexes ending the pauses represent “pseudo-escape beats” resulting from conduction of the second-last P wave over the slow AV nodal pathway. See text for discussion.
Heart Rhythm  , DOI: ( /j.hrthm )
Copyright © 2015 Heart Rhythm Society Terms and Conditions