Myopotential Sensing by a Dual Chamber Implantable Cardioverter Defibrillator:

Abstract

Although modern ICDs have proven to be highly effective in detecting and terminating malignant tachyarrhythmias, the opportunity for improving their detection specificity remains.

Analysis of the Lead Sensitivity Distribution in Implantable Cardioverter Defibrillator

“…In order to extract heart rhythm, ICD currently estimate the duration of the RR interval on a beat-to-beat basis by sensing ventricular activations in EGM signals, which are continuously recorded by intracardiac leads. As a consequence, ICD overall performance depends on the ability of intracardiac leads to measure ventricular bioelectric events and reject other biolectric events of non-ventricular origin, which include myopotentials (Deshmukh & Anderson, 1998;Kowalski et al, 2008;Sandler & Kutalek, 1994;Schulte et al, 2001) and pacing stimulus artifacts (Menz et al, 1998). It is widely acknowledged that lead design can affect EGM sensing and therefore ICD performance.…”

“…Other studies have addressed the effects on EGM sensing, of artifacts originating from non-ventricular bioelectric sources. For example, inappropriate ICD discharges have been ascribed to myopotentials oversensing (Deshmukh & Anderson, 1998;Kowalski et al, 2008;Sandler & Kutalek, 1994;Schulte et al, 2001). Pacing stimulus artifacts, which are often associated to ICD undersensing, have been found to be greater in integrated than in dedicated bipolar leads (Menz et al, 1998).…”

Inappropriate detection in an implantable cardioverter defibrillator after generator change

“…Diaphragmatic myopotentials usually present as low‐amplitude, high‐frequency signals, oversensed after ventricular pacing or long diastoles, when the dynamic sensing threshold is near minimum . DMO should especially be considered in cases of bradycardia‐dependent oversensing only on the ventricular channel, especially in patients with integrated bipolar leads, and in case of lead positioned at the right‐ventricular apex . DMO has been described with various device manufacturers.…”

Should all implantable cardioverter defibrillators for ventricular arhythmias be dual-chamber devices?

“…The availability of atrial electrogram enables the device to compare the number and timing of each atrial event in relation to the ventricular event. Current dual-chamber algorithms are mostly constructed based on the atrial rate, ventricular rate, and the timing relationship of their electrograms [9••,10•, [11][12][13][14][15][16]. Although these algorithms are reported to be highly sensitive and specific, controversies exist as to whether dual-chamber ICDs have advantages over single-chamber devices in reduction of inappropriate therapies.…”