Medtronic PROTECTA XT DR D314DRG, Руководство для клиницистов

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Figure 185. Synchronous delivery of defibrillation
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200 ms
Confirmation Interval
ECG
Marker Channel
1 The device has detected VF. It charges its capacitors for defibrillation and confirms VF using
the confirmation interval. In this example, ATP During Charging is disabled.
2 The device completes charging and starts synchronization while continuing VF confirmation.
3 On the second tachyarrhythmic event after charging, the device delivers the defibrillation
therapy.
9.1.2.6 Synchronizing subsequent defibrillation therapies
If the first defibrillation therapy fails to terminate a VF episode, the device attempts to
synchronize each subsequent defibrillation therapy to a sensed ventricular event. If
synchronization is not possible, the device delivers the defibrillation therapy
asynchronously.
Once the capacitors are charged to the programmed energy, the device starts a 900 ms
synchronization window. If a qualified sensed ventricular event occurs during this window,
the device delivers the defibrillation therapy synchronized to the event. Otherwise, the
device delivers the therapy asynchronously after 900 ms (see Figure 186).
Any sensed ventricular event qualifies for therapy delivery unless it occurs in the refractory
period or in the atrial vulnerable period. If an event occurs in the refractory period, the device
continues to attempt to synchronize. If an event occurs in the atrial vulnerable period, the
device changes the synchronization window to 500 ms and continues to attempt to
synchronize. A subsequent sensed ventricular event that occurs outside the refractory
period qualifies for therapy delivery even if it occurs in the atrial vulnerable period.
Medtronic PROTECTA™ XT DR D314DRG
362 Clinician Manual