Loss of biventricular pacing following a noise detection on the right ventricular lead.

Patient

54 years old man implanted with a triple chamber defibrillator Protecta XT CRT-D for ischemic cardiomyopathy with a wide QRS ; Device interrogation demonstrating an episode of noise appropriately diagnosed by the device ;

Trace

Plots

variable ventricular rhythm ;
very short cycles close to the post-ventricular ventricular blanking limit ;
detection of VT/VF suspended ;
end of the episode ;

Tracing

very high amplitude signals saturating the amplifiers and detected in the VF zone; interruption of the biventricular pacing
interruption of the detection, the device has made the diagnosis of noise oversensing (N : noise) ;

Text

episode classified as noise by the device ;

Comments

The most recent triple chamber defibrillators from Medtronic benefit of the new discrimination platform including the RV lead noise discrimination algorithm, the RV lead integrity alert, the TWave discrimination algorithm, and the wavelet added to the PR Logic… This tracing illustrates the interest of the RV lead noise discrimination algorithm that avoids in this patient several inappropriate shocks. The RV lead noise discrimination algorithm differentiates RV lead noise from VT/VF by comparing a far field EGM signal to near field sensing. If lead noise is identified (tachycardia detected on the bipolar EGM but not on the far field EGM), VT/VF detection is withheld, and an RV Lead Noise alert is triggered.

Pacing & Defibrillation

ECG

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