Autoseuil Saint Jude Medical

Type de tracés: 


Voici un tracé capté par "chance"...

Je change un boitier de CRT-P à un patient dépendant. En fin de procédure, je teste les autoseuils. Le test pour le VD recommande l'utilisation de l'autoseuil. L'autoseuil est réalisé et la valeur trouvée par l'appareil est de 0,5V.

Cependant, je laisse trainer un oeil (il faut toujours laisser trainer un oeil) et je vois ce tracé.

Qu'auriez-vous fait ? Personnellement, je n'ai pas activé et je n'activerai pas l'autoseuil VD chez ce patient. Avez-vous déjà eu ce genre de problème ?


Why such a short AV delay?

I just don't understand why He didn't did Ventricular Protection pacing at the 2nd missed capture.

Other wise the algorythm seems to be working fine.

Best wishes,


Probably, as the patient did an atrial premature beat, the device saw still the activity of the T wave , the repolarisation and was mistaken in thinkinkg that he had capture.

But I think you can keep your faith on autocapture- there shouldn't be any clinical event - and he still has LV pacing.

Hi Remi,

This is an auto RV pacing threshold, using a short AVD to avoid fusion. Loss of capture is recognized twice (PDC) but missed once (last AS-VP, before AP-VP). The question is why? The first V EGM following "PDC" is different, so probably a PVC (dependant patient). This should have something to do with this unusual sequence.


Hello there:

The first channel is D2, the second is Markers and the third is marker is A bipolar (very important to notice this marker), the test is program to perform TWO PACED BEATS before going down in the threshold so at 0,25 V it performs AS and VP with loss of capture (PDC) but actually captures the V, then it performs AS and VP with actual loss of capture, it ends the algorithm and performs AP with maximal output (that's why the third channel shows that beat, which is atrial stimulation with a high amplitud) and then VPP (what actually happens is that captures the ventricle and the signal in the fourth channel looks thinner because the second P of the VPP might be generating a sort of fusion that makes the repolarization of the seventh beat to look smaller.
I think the algorithm and system are working fine, I think what makes it confusing is the fact that the third channel is the atrial channel. 

I agree that the missed beat could be a PVC.

Big hug from Mendoza, the wine region in Argentina. I hope to have the chance to exchange some wines someday, specially our Malbec.


If I look at the last channel which is V unipolar, I don't see V capture after the second V pacing at 0.25V. The farfield signal on the Atrial channel is also missing, so for me there is definitively no V capture and the algorithm didn't see it.

I would be more than happy to taste your famous Malbec! When will do you come to visit us Dr Palazzo?


Yes. I looked it up again. It is not actually working. An evoked test should be done to see if autoseuil
can be put on or not. With this tracing I would not put it on.