Failure to shock: What is the mechanism?

Abstract

Background: The Biotronik DX lead is an attractive option due to its floating atrial bipole and its noninferiority compared to dual-chamber defibrillators.

Methods: We describe the case of atrial undersensing by the DX lead resulting in failure of the device to appropriately treat a slow ventricular tachycardia.

Conclusion: This case underlies the importance of understanding the limitations to each lead technology as well as the underlying assumptions inherent to detection enhancement algorithms.

Keywords: defibrillation-ICD; ventricular tachycardia.