Specifications

7 x 9 inches (178 mm x 229 mm)
Medtronic Confidential
Refer to the “Reference man.” category in doc#163256 for Printing
Instructions.
196407001 Rev A
The Prodigy pacemaker’s timing in dual chamber modes can be
summarized by the following rules:
■
In the DDDR, DDIR, DVIR, DDD, DDI, and DVI modes, an atrial
pace starts a PAV that times out only in the absence of a sensed
ventricular event. That is, the VA interval always begins with the next
sensed or paced ventricular event, whichever comes first. In the VDD
mode, an atrial sense starts a SAV that times out only in the absence of
a sensed ventricular event.
■
In the DDDR, DDD, and VDD modes, a nonrefractory sensed atrial
event starts an SAV that times out only in the absence of a sensed
ventricular event. That is, the VA interval (V-V escape interval in
VDD mode) always begins with the next sensed or paced ventricular
event, whichever comes first.
■
In the DDDR, DDIR, DVIR, DOOR, DDD, DDI, and DVI modes,
VA interval adjustments are made on a beat-by-beat basis to maintain a
constant atrial pacing rate (A-A timing). These VA adjustments are
made whenever:
The AV interval is shorter than the PAV interval, which will be
started by the next scheduled atrial pace (next scheduled PAV
interval).
■
When the Rate Adaptive AV feature is programmed ON in the DDDR,
DDD, DDIR, DVIR, DOOR or VDD mode, the pacemaker modifies
the AV intervals (scheduled PAV or SAV intervals) step-by-step as the
heart rate increases or decreases. The scheduled PAV or SAV intervals
are determined at every V-pace or nonrefractory V-sense event. The
resulting operating PAV interval is based upon the current sensor rate,
whereas the operating SAV is based upon the mean atrial rate (a
running average atrial rate).
E-16 Prodigy Reference Information
9879EN-E_9501043EN/CTC.qxd 5/10/99 11:40 Page E-16