ventricular safety standby
Pronunciation: vee-ess-ess
Also written as: VSS
Pacing mode triggered when ventricular oversensing is detected, providing backup pacing to prevent asystole during sensing malfunction.
Full Definition
Ventricular safety standby (VSS) is a protective pacing feature that activates when a cardiac device detects rapid, irregular sensing that may indicate lead malfunction or electromagnetic interference rather than true cardiac activity. When triggered, the device switches to a backup pacing mode to ensure continued ventricular stimulation and prevent potentially life-threatening asystole. Medical editors must understand VSS activation criteria, duration, and documentation requirements as this feature indicates potential device or environmental problems requiring clinical evaluation.
Usage
Usage note: Indicate trigger reason when known; distinguish from other safety modes; note clinical implications of activation.
In Context
- "Ventricular safety standby activation indicated potential lead fracture requiring urgent device evaluation." — Emergency consultation note
- "The device automatically entered VSS mode during MRI scanning to maintain pacing support despite electromagnetic interference." — MRI safety protocol