1. Narrow QRS Complex Tachycardias
Stephen J. Pieper, M.D., Marshall S. Stanton, M.D. 
Mayo Clinic Proceedings 
Volume 70, Issue 4, Pages (April 1995)
DOI: /
Copyright © 1995 Mayo Foundation for Medical Education and Research Terms and Conditions

2. Fig. 1
Top Panel, Schematic representation of short RP tachycardia. Arrows = P waves occurring in ST segment shortly after QRS complex. Distance from onset of QRS to P wave is much less than distance from P wave to subsequent QRS; thus, the designation “short RP tachycardia” is used. Bottom Panel, Schematic representation of long RP tachycardia. In this case, P waves (arrows) precede each QRS complex by a short interval. Therefore, distance from onset of QRS to P wave considerably exceeds distance from P wave to subsequent QRS. Hence, the label “long RP tachycardia” is appropriate.
Mayo Clinic Proceedings  , DOI: ( / )
Copyright © 1995 Mayo Foundation for Medical Education and Research Terms and Conditions

3. Fig. 2
Schematic representation of operative circuit in atrioventricular (A V) nodal reentrant tachycardia. A, Excitation wave front has entered AV node and blocked in the fast pathway; it continues to conduct down a slow pathway. B, Excitation wave front has reached a final common pathway in AV node; it not only exits AV node but also proceeds retrograde through previous site of antegrade block in fast pathway. C, Excitation wave front has reentered the slow pathway and perpetuated excitation around reentrant circuit.
Mayo Clinic Proceedings  , DOI: ( / )
Copyright © 1995 Mayo Foundation for Medical Education and Research Terms and Conditions