User's Manual

28
Pacing Types – Modes
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Figure 6: Prevention of pacemaker-mediated tachycardia in VDD mode
AAI Mode, VVI Mode
The AAI and VVI single-chamber pacing modes are used for atrial or
ventricular demand pacing. In each case, pacing and sensing only
occur in either the atrium (AAI) or the ventricle (VVI).
The basic interval is started by a sense or pace event. If there is a
sense event before the end of the basic interval, pulse delivery is
inhibited. Otherwise, pacing takes place at the end of the basic
interval.
AOO Mode, VOO Mode
In these pacing modes, pulses are emitted asynchronously in the
atrium (AOO) or ventricle (VOO). When using VOO or AOO mode, the
risks associated with asynchronous ventricular pacing must be
considered.
DOO Mode
Asynchronous AV-sequential pulses are delivered in this pacing mode.
When using DOO mode, the risks associated with asynchronous
ventricular pacing must be considered.