Arrhythmias & electrophysiologyCohort study

Output-dependent electrocardiographic criteria to distinguish Bachmann bundle area pacing from high atrial septal pacing: Validation with coronary sinus mapping

Heart RhythmPublished

  • prospective study
  • validation with coronary sinus mapping

Authors' conclusion

Output-dependent ECG transition, particularly changes in P-wave morphology, Stim-PWPTII, and CS activation timing, provides practical and reproducible intraprocedural markers of preferential interatrial conduction. These findings represent physiologic evidence rather than definitive proof of direct Bachmann bundle capture.

Study context

Population
Patients undergoing attempted Bachmann bundle area pacingpatients undergoing attempted bachmann bundle area pacing (BBAP)
Participants
Fifty-seven patients
Exposure
BBAP vs high atrial septal pacing (HASP) without abrupt transition

Main finding

As reported in the abstract

Abrupt output-dependent P-wave morphology transitions

Abrupt output-dependent P-wave morphology transitions

41 of 57 patients (71.9%)

Observational data: associations, not effects.

Further findings

OutcomeP value
PWD, Stim-PWPTII and Stim-CSd intervals · shorter with BBAPall P < .001

Final pacing site with physiologic markers consistent with BBAP after mapping-guided lead repositioning

Final pacing site consistent with BBAP
56 of 57 patients (98.2%)

ΔStim-PWPTII of ≥10 milliseconds

Consistently separated the study-defined BBAP and HASP groups within this cohort
  • should be considered hypothesis-generating and requires prospective validation

Original publication

Output-dependent electrocardiographic criteria to distinguish Bachmann bundle area pacing from high atrial septal pacing: Validation with coronary sinus mapping. Heart Rhythm. Published 3 August 2026. doi:10.1016/j.hrthm.2026.07.037

Summarised from the published abstract; every number is checked against it