Estella Pulse Generators - BIOTRONIK USA - News

Estella Pulse Generators Technical Manual 53CautionPulse Amplitude—Programming of pulse amplitudes, higherthan 4.8 V, in combination with long pulse widths and/or highpacing rates can lead to premature activation of the replacementindicator. If a pulse amplitude of 7.0 V or higher is programmedand high pacing rates are reached, output amplitudes may differfrom programmed values.Programming Modifications—Extreme programming changesshould only be made after careful clinical assessment. Clinicaljudgment should be used when programming permanent pacingrates below 40 ppm or above 100 ppm.7.3.2 Pulse WidthThe selected pulse width determines the duration for which theprogrammed pulse amplitude will be applied to the heart. The pulsewidth is independently programmable (up to 1.5 ms) for the atrial andventricular channels. Pulse width remains constant throughout theservice life of the pulse generator.NOTE:When VCC is programmed to ON or ATM, the pulse width cannot beprogrammed to a value higher than 0.4 ms.7.4 Automatic Sensitivity Control (ASC)The parameter “sensitivity” is used to set the pulse generator’sthreshold for detecting intracardiac signals. The lower the programmedsensitivity values the higher the device’s sensitivity.If intracardiac signals are of low amplitude, a change to a highersensitivity (lower value) may be indicated. Conversely, if the sensingamplifier is responding to extraneous signals, such as artifacts orinterference, a change to a lower sensitivity (higher value) may resolvethe difficulty. The sensitivity values for the atrial and ventricular channelsare independently programmable or automatic sensing control can beutilized. With Unipolar programming, the highest possible sensitivitysetting is 0.5 mV.The Automatic Sensitivity Control (ASC) feature allows the pulsegenerator to automatically measure the peak amplitude of a sensedevent and adapts the sensing threshold accordingly. After each senseddetection (electrogram is above actual threshold for 2 consecutivesamples) the ASC is starting the detection hold-off period of 121 ms inthe ventricle (atrium 101 ms) and detects within the first 80 ms of this