Download decremental

14 yr old boy
Ebstein’s anomaly
Marked displacement of septal
tricuspid leaflet.
RA/RV moderately dilated.
Mild TR
Recurrent paroxysmal palpitations
Inputs from Martin Green and
Chandrashekhar
Comment.
One thing I have always taught my fellows is beware the Ebstein's who does not have wide RBBB.
In Ebsteins anomaly if the ECG shows absence of RBBB, we should always think of right free wall AP
Analyse- Normal intervals
40 ms
CS pacing- comment
During CS pacing the wavefront reaches the AV node earlier than the right free wall AP.
Hence RBBB is evident
RA pacing – comment. Now the wavefront goes predominantly through the AP, hence there is more
preexcitation. Note the decremental AP conduction (Stim-QRS gets longer as preexcitation increases)
Analyse- RBBB during CS pacing, disappears during sinus rhythm
Interpret- Concentric and decremental VA conduction
Tachy initiated- describe. With CS pacing RBBB appears then it gets blocked in the AV Node and
goes through the right free wall AP, initiating an antidromic tachycardia - LBBB with superior axis
Intracardiacs during tachy- discuss. IC EGMs showing the WCT- A in His catheter is not
clearly seen. There is no RV catheter to say whether V at RV apex is earlier when
compared to His V. Also RB potentials are not recorded
Tachy termination- any further insight? The HISP records A and H in sinus rhythm.
During tachy, the H is buried in the V and the A in His is the earliest. The tachy terminates in the AV node.
J Cardiovasc Electrophysiol. 1998 Sep;9(9):1012-4.
Preexcited tachycardia in a patient with Ebstein's anomaly: is the
preexcitation manifest during sinus rhythm?
Vora AM1, Lokhandwala YY.
Isoprenaline-discuss. AP automaticity is enhanced
Diagnosis confirmed? Yes. A late (His-refractory) RA APD advances (
and resets ( ) the tachycardia
) the next QRS
Again… same thing is shown
Signal at RF site- Mahaim potential (M)
M
M
RF site-LAO 40. SR2 sheath used.
RF site-PA view
RF energy-Voila! As the AP is eliminated, RBBB appears.
No tachy inducible after this
Final diagnosis:
Ebstein’s anomaly.
Mahaim-like right lateral atriofascicular AP with ADT.
Successful RF ablation.