Fixation beats – a novel marker for reaching the left bundle branch area during deep septal lead implantation

Abstract

Introduction: One of the challenges of left bundle branch (LBB) pacing is to place the pacing lead deep enough in the septum to obtain capture of the LBB, yet not too deep to avoid perforation. We hypothesized that the occurrence of the ectopic beats of qR/rsR morphology in V1 lead (fixation beats) during the lead fixation would predict that the final desired intraseptal lead depth was just reached, while the lack of fixation beats would indicate too shallow position, and need for more lead rotations. Methods: Consecutive patients during LBB pacing device implantation were analyzed retrospectively and then prospectively with respect to the occurrence of the fixation beats during each episode of lead rotation. We compared the presence of fixation beats during the lead rotation event directly before the LBB capture area depth was reached versus during the events before intermediate/unsuccessful positions. Results: A total of 339 patients and 1278 lead rotation events were analyzed. In the retrospective phase, the fixation beats were observed in 327/339 of final lead positions and in 9/939 of intermediate lead positions (p<0.001). The sensitivity, specificity, positive and negative predictive value of the LBB area fixation beats as a marker for reaching the LBB capture area was 96.4%, 99.0%, 97.3% and 99.0%, respectively. In the prospective, fixation-beats-guided, implantation phase the fixation beats were observed in all patients and only at the LBB capture depth. Conclusions: Monitoring fixation beats during deep septal lead deployment can facilitate the procedure and possibly increase the safety of lead implantation.

Comparing Ventricular Synchrony in Left Bundle Branch and Left Ventricular Septal Pacing in Pacemaker Patients

“…Determining the exact depth within the septum remains difficult, since it is usually not possible to perform ventricular pacing during screwing with conventional connector cables and the exact penetration depth is unclear from just the fluoroscopic images. However, Jastrebski et al [ 19 ] has recently shown that the ventricular ectopy that becomes apparent as a result of screwing is present in 96% of the cases and that these so-called fixations beats are identical to the paced QRS morphology. Therefore, these fixation beats can help to identify the depth of the LBBP lead and appearance of the r’ morphology can be interpreted as a warning sign that the left side of the interventricular septum is reached.…”

Physiology-Based Electrocardiographic Criteria for Left Bundle Branch Capture

“…The LBB implantation procedure was described by us and others elsewhere. 1-7 In order to develop LBB capture criteria, only patients with direct evidence of capture of the LBB were included in the study. Such a situation was considered to be the case when there was QR/rSR’ paced QRS morphology in lead V1, with at least one of the following three conditions fulfilled:…”

Left Bundle Branch Area Pacing guided by Continuous Uninterrupted Monitoring of the unipolar Pacing Characteristics.

“…In the early development of LBBAP, Jastrzebski and others, using the lumen-less Medtronic 3830 lead, proposed to continuously pace mapping during LBB implant by keeping the crocodile connector onto the lead CP. [10][11][12] Unfortunately, given the lack of commercially available revolving connectors for the distal pin, practical application of this technique was limited by the unstable connection and more importantly by the significant risk of fracture between the distal pin and the inner conducting wire. Accordingly, further practical development focused on the recognition of "irritative" PVCs generated during the transseptal screwing of the LBB lead.…”