# Heart Rate Threshold Settings for Ventricular Tachycardia in Patients with Wearable Cardioverter-defibrillators

## TL;DR

This paper studies the optimal heart rate threshold for wearable cardioverter-defibrillators to detect ventricular tachycardia and prevent unnecessary shocks.

## Contribution

The study identifies a 150 bpm threshold for detecting ventricular tachycardia in wearable cardioverter-defibrillators.

## Key findings

- 15% of appropriate shocks were delivered for ventricular tachycardia at 150–170 bpm.
- 30% of patients with ventricular tachycardia at 150–170 bpm experienced loss of consciousness.
- A 150 bpm detection threshold is recommended for wearable cardioverter-defibrillators.

## Abstract

The wearable cardioverter-defibrillator (WCD) uses programmable heart rate (HR) and detection time to determine the need for shock delivery, but the optimal ventricular tachycardia (VT) HR detection zone is unknown. The LifeVest™ (ZOLL Medical, Chelmsford, MA, USA) WCD has a default VT detection rate of 150 bpm. We found that 15% of appropriate shocks among WCD recipients were delivered for VT 150–170 bpm and that 30% of these patients experienced loss of consciousness. Based on these findings, a programmed VT detection threshold of 150 bpm should be considered.