Inappropriate therapy due to noise immediatly after S-ICD implant... (Resolved).

Trace category: 
EGM
Device/Field: 
ICD
Company: 
Boston Scientific

Just want to share with you this tracing of a yong adult implanted with an S-ICD in primary prevention. 

Immediatly after the implant, the patient got shocked inappropriately  due to artifacts and noise detected by the device. 

The next day, the problem was completely resolved with no intervention. 

Will you guess what was the mistake performed by the surgeon that explained this...? 

I promess, I will post the solution! 

All best, JB

 

 

The problem was resolved the next day with an intervention...

This is a sensing problem. 

Did you change the sense polarity

Hello

In OR sensing was programmed as secjndary-in follow up you saw a changes in EGM when change to primary-alternate!

Surgeon explain this how appropriate shock!?

In this case, artifacts are seen on the tracing and sensed by the device, which explained why the patient got inappropriately shocked. 

Immediately after the shock, the noise has dissapeared. This suggest that the patient was performing any kind of activity that was stopped when he received the shock.

In this case, no specific frequency emerge from the analysis of the noise but it seems rather low and cahotic. Patient interrogation revealed that he was exercising (rawing) when he received the shock.   

At device interrrogation, both the primary, secondary and alternate vectors are OK!

However, the device was placed sub-cutaneously and not fixed. Moreover, the pocket was too large and the device has moved anteriorely. During the consultation, abdominal works reproduced intermittent noise on the primary and secondary vector but not on the alternate.

The device was replaced in the intermuscular space and fixed to the muscle. No futher problem occured. 

Final disgnosis: Inappropriate therapy due to musclar artifacts (myopotentials) related to the anterior and inferior migration of the device that has'nt been fixed in the pocket.