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Long-Term Outcome of Patients with Bifascicular Block and Unexplained Syncope Following Cardiac Pacing

Matthew M Kalscheur1, Paolo Donateo2, Kevin E Wenzke1

  • 1Division of Cardiovascular Medicine, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin.

Pacing and Clinical Electrophysiology : PACE
|August 28, 2016
PubMed

Insights

Cardiac pacing for bifascicular block and syncope is reasonable, but recurrence is common with empiric pacing. Pacemakers guided by electrophysiological studies or loop recorders show better long-term outcomes for syncope patients.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Medical Devices

Background:

  • Bifascicular block (BF-B) with syncope is an indication for cardiac pacing when other causes are ruled out, per ACC/AHA/HRS guidelines.
  • Long-term outcomes of pacing in this patient population require further assessment.

Purpose of the Study:

  • To evaluate the long-term outcomes of patients with bifascicular block and unexplained syncope who underwent cardiac pacing.
  • To compare the recurrence of syncope based on the method of pacemaker implantation (empiric vs. guided by electrophysiological study or loop recorder).

Main Methods:

  • A retrospective study of 43 patients with syncope and BF-B who received pacemakers between 2009 and 2015.
  • Patients were divided into empiric pacing group and those who received a pacemaker after a positive electrophysiological study (EPS) or insertable loop recorder (ILR) documentation of transient atrioventricular block (AVB).
  • Follow-up averaged 31 months to assess syncope recurrence and progression to high-degree AVB.

Main Results:

  • Syncope recurred in 16% of patients over a mean follow-up of 31 months.
  • Empiric pacing was associated with a significantly higher rate of syncope recurrence (27%) compared to pacing guided by EPS/ILR (0%; P=0.02).
  • Progression to high-degree AVB occurred in 37% of patients, with no significant difference between the groups.

Conclusions:

  • Syncope recurrence is not uncommon in patients with BF-B receiving pacemakers.
  • Pacemaker implantation guided by positive EPS or transient AVB documentation via ILR is associated with no syncope recurrence, unlike empiric pacing.
Abstract

Keywords:
EP studybifascicular blockimplantable loop recorderpacemaker

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