Use Instructions

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• LS Out of Alert: A local sense event detected after the end of the Local Sense
Alert Window triggers an LS Out of Alert condition. The Local Sense Alert
Window is the time interval during which the leading edge of valid LS events
triggers CCM therapy delivery. How this is programmed is detailed in Section
10.7.3.
• Ventricular Tachycardia (VT): Whenever the ventricular tachycardia rate limit is
exceeded, CCM therapy delivery is automatically inhibited. Using the
OPTIMIZER Smart Mini Programmer application, the ventricular tachycardia rate
limit can be set to one of 25 possible values between 62 bpm and 110 bpm. CCM
therapy delivery is always inhibited when ventricular tachycardia rate limit is
exceeded.
Note: This parameter is active only when the OPTIMIZER Smart Mini IPG is in
OVO-LS-CCM mode.
• Atrial and ventricular noise: Despite various methods for detecting and filtering
noisy signals implemented in the OPTIMIZER Smart Mini IPG, noise from
powerful electromagnetic sources (e.g., from portable telephones, radio
transmitters, etc.) as well as noise from physiological events (e.g., myopotentials,
etc.) can interfere with the detection of cardiac events.
Any time higher rate signals (greater than 11.6 Hz) are detected on the atrial or
ventricular channel, the control logic of the OPTIMIZER Smart Mini IPG assumes
the presence of noise and declares an A/V noise condition. CCM therapy delivery
is always inhibited if atrial or ventricular noise is detected.
10.7 Local Sense
Detected local electrical activity of the ventricular myocardium with respect to right ventricle (RV)
electrical activity is known as Local Sense (LS) events.
10.7.1 Assignment of Local Sense Channel
The OPTIMIZER Smart Mini IPG features the option of allowing the Local Sense (LS)
channel to be assigned to either implanted ventricular lead. Using the OPTIMIZER Smart
Mini Programmer application, the V1 or V2 lead can be designated as the LS channel.
Accordingly, when one ventricular lead is designated as the LS channel, the other
ventricular lead is automatically designated as the RV channel.
10.7.2 CCM Triggering Based on Local Sense Events
Delivery of CCM therapy is dependent on the intrinsic myocardial electrical activity in the
vicinity of the designated Local Sense (LS) channel. The LS channel is configured to
sense the electrical activity of a small, localized area of the heart (near the fixation site of
the designated ventricular electrode). In response to this sensed activity, the OPTIMIZER
Smart Mini IPG evaluates the myocardial electrical signal to determine whether it meets
the criteria defined by the set of LS parameter values programmed into the device. If the
criteria are met, then the IPG delivers CCM therapy. Within a cardiac cycle, the timing of
the signal detected by the ventricular lead designated as the LS channel, especially with
regards to the R wave, is the main criterion for the OPTIMIZER Smart Mini IPG to classify
the cycle as normal or abnormal. CCM therapy is not delivered during cycles classified as
abnormal.
10.7.3 Local Sense Alert Window
When the internal logic of the device detects ventricular events corresponding to cardiac
cycles not classified as abnormal because of noise, atrial tachycardia, or suspected
PVCs, it will open a Local Sense Alert Window. The Alert Window can be inside the AV
interval, inside the VA interval, or partially inside the AV and partially inside the VA
interval.
The first event detected within the window serves as a trigger for CCM therapy delivery.