VF zone
Also written as: VF — ventricular fibrillation
The highest rate detection zone in an ICD programmed to detect ventricular fibrillation and deliver high-energy shocks.
Full Definition
The VF (ventricular fibrillation) zone represents the fastest heart rate detection tier in implantable cardioverter defibrillator programming, typically set between 200-250 beats per minute or higher. When the device detects sustained rates in this zone, it bypasses discrimination algorithms and proceeds directly to high-energy defibrillation therapy. The VF zone is designed to provide rapid treatment for life-threatening ventricular fibrillation, where immediate defibrillation is crucial for survival. Programming of VF zone parameters requires careful consideration of the patient's underlying rhythm disorders and hemodynamic tolerance.
Usage
Usage note: Always capitalize 'VF' when used as abbreviation; distinguish from 'VT zone' which has different therapy algorithms.
In Context
- "The VF zone was programmed to 220 bpm to ensure rapid defibrillation for sustained arrhythmias." — ICD programming report
- "Analysis revealed appropriate VF zone detection with successful defibrillation on the first shock." — Arrhythmia episode review