User Manual

Lumax Technical Manual 85
Lumax 600/640 & 700/740 Models only
2.4.5 RV & LV Capture Control
RV & LV Capture Control uses the determined pacing threshold
to adjust the permanent pulse amplitude. The new permanent
pulse amplitude is composed of the determined pacing threshold
plus a safety margin (1.0 or 1.2 V) and is automatically
programmed in the ICD.
2.5 Ventricular Tachyarrhythmia Detection
The Lumax ICDs/CRT-Ds detect and measure the rate of sensed
cardiac signals to discriminate ventricular tachyarrhythmias from
supraventricular tachycardias, sinus rhythm or sinus bradycardia.
This is accomplished through programmable rate detection
parameters in the device. When a tachyarrhythmia is present, the
ICD/CRT-D classifies the arrhythmia and delivers the appropriate
therapy. If a tachyarrhythmia continues following the first therapy
attempt, then the ICD/CRT-D will redetect the tachyarrhythmia
and deliver subsequent therapies as necessary.
WARNING
Unwanted Shocks – Always program ICD therapy to OFF
prior to handling the device to prevent the delivery of serious
shocks to the patient or the person handling the device
during the implant procedure.
Classification of cardiac signals is accomplished primarily by
measuring the cardiac cycle length (R-R, P-R and P-P). In
addition, the ICD/CRT-D can also utilize abrupt changes in rate or
irregularity of the cardiac signal to further differentiate ventricular
tachyarrhythmias. Each detected ventricular tachyarrhythmia is
classified into one of the following zones:
 VT-1 Lower rate ventricular tachycardia
 VT-2 Higher rate ventricular tachycardia
 VF Ventricular fibrillation
Each rhythm class is programmable to a separate rate with the
zone limit defining the lowest rate in each class. The upper rate
limit of each class is equal to the zone limit of the next higher
class, creating a continuous range of rate classes.