BIOTRONIK Lumax DR ICD Series, Technical Manual, Page: 86 / 176

78 Lumax Technical Manual
Figure 5. Biphasic Waveforms
Both waveforms start at the calculated voltage, based on the
programmed energy level. After an exponential discharge
through the lead system to 40% of the initial charge voltage, both
shock waveforms switch polarity. At the second phase the:
•
Biphasic waveform discharges to 20% of the initial charge
voltage before the waveform is truncated
•
Biphasic 2ms waveform discharges the remaining energy
for two milliseconds before the waveform is truncated
Figure 5 provides a pictorial representation of both biphasic
waveforms.
BIOTRONIK recommends use of the standard Biphasic shock
waveform for initial defibrillation threshold testing. If testing
demonstrates high defibrillation thresholds, testing with the
Biphasic 2ms waveform is offered as a therapeutic alternative to
the standard Biphasic shock.
2.8.3.4 Shock Energy
The Lumax ICDs/CRT-Ds are designed to charge to the energy
selected on the programmer screen, but similar to all other
commercially available ICDs/CRT-Ds, the actual therapy
delivered is somewhat less depending on several factors
including the shock lead impedance. The first two shock energies
in each therapy class are programmable between 1 joules and
maximum energy for the device type. The energy of the second
shock is always greater than the first shock. The remaining
shock energies will be delivered at maximum programmable
energy.