User Manual

9 Product Description 
Diagnostic and Therapy Functions
Diagnostic and Therapy Functions
General overview All the systems have extensive features that allow quick diagnosis and delivery of
safe therapy for bradycardia conditions.
• Automatic functions make it easy and fast to implant, configure, and check the
pacemaker.
• Auto-initialization after implantation: The device recognizes the implanted leads
autonomously and sets the polarity. The automatic functions of the software are
activated after 10
min.
Diagnostics functions • Data from the last interrogations and follow-ups are recorded as well as
arrhythmia episodes; they are stored together with other data to assess the
state of both the patient and the device at any time.
• Continuous automatic below-threshold impedance measurements are
performed in the device independent of the pacing pulse in order to check the
lead for proper functioning.
• Once a telemetry connection has been established during a test procedure in an
in-office follow-up, the IEGM is displayed with markers.
Antibradycardia pacing • Sensing: The amplitudes of the P and R waves are measured in the implanted
device fully automatically and permanently to record varying amplitudes. The
sensitivity for the atrium and ventricle is adapted automatically on an ongoing
basis. The measurement data are averaged and the trend can be displayed.
• Pacing thresholds: Pacing thresholds are automatically identified in the device,
in single and dual-chamber devices the right ventricular, in triple-chamber
devices the right and left ventricular pacing thresholds. Capture control adjusts
the pulse amplitudes in such a way that every change of the pacing threshold
results in the patient being paced at an optimal amplitude.
• Timing: Pacing in the atrium is checked particularly carefully in dual and triple-
chamber devices by an automatic adaptation of the atrial refractory period in
order to avoid pacemaker-mediated tachycardia (Auto PVARP function:

the postventricular atrial refractory period is adapted automatically).
• Additional, special form of rate adaptation: An increased cardiac output
requirement is detected using physiological impedance measurement.

The measuring principle is based on contractile changes (ionotropy) of the
myocardium (CLS function: Closed Loop Stimulation). Rate adaptation is
automatically initialized and optimized in CLS mode.
• Ventricular pacing suppression with devices from the 8 series: Unnecessary
ventricular pacing is avoided by promoting intrinsic conduction (Vp suppression
function). The device can adapt itself to conduction changes. In the case of
intrinsic conduction, the device switches from a DDD(R) to an ADI(R) mode.
• In the course of the follow-up, an automatic test of the AV delay is performed to
improve the heart performance. AV delays are calculated; the optimum values
can be applied.