Answers to ECG of the Week Question

20 JAN 2014

1)          What information is gained with entrainment of the tachycardia from the mid coronary sinus and the eustachian ridge?

A.      Entrainment - A pacing technique that is done within the reentrant loop which can drive the tachycardia rate. It helps identify where the loop is located.

In our case, Entrainment from the mid coronary sinus revealed a Post Pacing Interval (PPI) of 43mS which means it is out of the circuit.  Entrainment from the Eustachian ridge revealed a Post Pacing Interval (PPI) of 00mS, which shows the Eustachian ridge was within the circuit.

 

2)          What structure does this Rhythm use to maintain its circuit?

A.      The cavo-tricuspid isthmus

 

       3)      What rhythm is this?

                  A. Typical clockwise atrial flutter.

 

4)      What location would be ablated in order to terminate this rhythm and restore Sinus Rhythm?

A.      Ablation of the cavo-tricuspid isthmus.