Pacing system analyzers to guide conduction system pacing implantation procedures: A comparison study of intracardiac and surface signals with an electrophysiology recording system.

Background: Left bundle branch area pacing (LBBAP) needs confirmation of left conduction system capture assessed by testing of different electrical parameters. Guidelines recommend the use of an electrophysiology recording system (EP-RS) to guide conduction system pacing procedures. However, some experienced centers perform LBBAP procedures without an EP-RS.

Objective: We aimed to assess whether LBBAP criteria can be measured by the signals provided by the pacing system analyzers (PSAs) as a surrogate for the EP-RS to simplify and universalize the technique.

Methods: This was an observational, prospective, multicenter study assessing the current LBBAP criteria using the PSA compared with the EP-RS during conduction system pacing procedures.

Results: A consecutive 108 patients were included. Baseline QRS duration was 130 ± 29 ms in the EP-RS vs 128 ± 29 ms in the PSA (P = .7). An initial W morphology in V was noted in 88% of patients with the EP-RS vs 86% of patients with the PSA (P = .7) during unipolar pacing. The QRS duration (122 ± 17 ms vs 123 ± 19 ms; P = .7), the R-wave peak time interval in V (80 ± 13 ms vs 79 ± 14 ms (P = .9), and the V-V interpeak interval (39 ± 16 ms vs 38 ± 17 ms (P = .7) were superimposable in the EP-RS compared with the PSA. Pearson coefficients for the last 2 criteria were 0.85 (P < .0001) and 0.94 (P < .0001), respectively. According to the current criteria, 91.5% of patients received a successful LBBAP implant using the EP-RS. Based on the PSA measurements, 96.6% of these patients met LBBAP criteria.

Conclusion: Criteria for LBBAP can be assessed by PSAs with high accuracy. These results provide the basis for the usefulness of the PSA to guide LBBAP procedures.