Chronic extraction of stylet-driven leads implanted at the left bundle branch area in a pre-clinical model
Robert D Schaller1, Eric A Johnson2, Raymond H Schaerf3
1Electrophysiology Section, Division of Cardiology, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
Background:
Implantation of cardiac pacemaker leads in the left bundle branch area (LBBA) has been increasingly adopted into clinical practice, driven by the goal of leveraging the natural conduction system to achieve physiologic cardiac pacing. Long-term management of pacemaker leads may require lead extraction to address infection or device malfunction, yet limited clinical data exist on the extraction of LBBA leads chronically implanted deep within the interventricular septum.
Objective:
The objective of the study is to assess the chronic extractability of a new stylet-driven lead implanted in the LBBA in a pre-clinical model.
Methods:
A pacing lead recently approved for LBBA pacing (UltiPace) was implanted in the LBBA of 6 canines and extracted after a dwell time of 19 months. Retraction of the extended helix was attempted, followed by measurement of extraction force using a force gauge.
Results:
Leads were successfully extracted in 5 out of 6 canines without the use of additional extraction tools other than a locking stylet. In successfully extracted leads (5/6), attempted helix retraction resulted in partial retraction in 3 leads and unsuccessful retraction in 2. Overall average linear tensile extraction force was 0.95 ± 0.54 lbf. The partially retracted group included the lead that required the least force (0.20 lbf) and the unretracted group included the lead that required the most force (1.70 lbf).
Conclusion:
Overall extraction success of UltiPace stylet-driven leads implanted in the LBBA was high, with extraction forces comparable to prior canine model extraction studies of leads implanted in the apex of the right ventricle.
