Medtronic PROTECTA XT DR D314DRG, Руководство для клиницистов

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Figure 197. Example of a cancelled cardioversion therapy
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ECG
Marker Channel
Confirmation interval
Normal events
1 2 3 4
1 The device has detected VT and starts charging its capacitors for cardioversion.
2 The device confirms the tachyarrhythmia using the confirmation interval.
3 The VT spontaneously terminates, and normal sinus rhythm resumes.
4 When 4 of the last 5 events are “normal events”, the device stops charging its capacitors.
9.3.2.4 Synchronizing cardioversion after charging
After charging ends, the device continues to confirm the presence of the tachyarrhythmia.
If the tachyarrhythmia persists, the device attempts to deliver the cardioversion therapy. If
the tachyarrhythmia changes, the device aborts the therapy.
To deliver the cardioversion therapy, the device attempts to synchronize it to a nonrefractory
ventricular event that meets one of the following conditions:
●
The event is the second tachyarrhythmic ventricular event after charging, and it is
outside the atrial vulnerable period.
●
The event is the third tachyarrhythmic ventricular event.
Note: The system defines the atrial vulnerable period as a 250 ms window that extends
from 150 ms to 400 ms after a sensed atrial event. A cardioversion therapy delivered during
this period might induce an atrial tachyarrhythmia. If a cardioversion delivery is scheduled
to be delivered during this period, it is postponed until the next qualifying event.
The device continues to attempt to synchronize until it delivers the cardioversion therapy or
it fails to confirm the presence of the tachyarrhythmia and cancels the therapy.
Medtronic PROTECTA™ XT DR D314DRG
Clinician Manual 383