Clinical outcomes of various management strategies for symptomatic bradycardia

Objective: To determine clinical outcomes of various management strategies for reversible and irreversible causes of symptomatic bradycardia in the inpatient setting. Design: Retrospective observational study. Setting: Emergency room and inpatient. Participants: Patients presenting to the emergency department with symptomatic bradycardia. Methods: We retrospectively reviewed electronic health records of 518 patients from two Mayo Clinic campuses (Rochester and Phoenix) who presented to the emergency department with symptomatic bradycardia (heart rate ≤50 beats/minute) from January 1, 2010 through December 31, 2015. Sinus bradycardia was excluded.The following management strategies were compared: observation, non-invasive management (medications with/without transcutaneous pacing), early permanent pacemaker (PPM) implantation (≤2 days), and delayed PPM implantation (≥3 days). Study endpoints included length of stay and adverse events related to bradycardia (syncope, central line–associated bloodstream infections, cardiac arrest, and in-hospital mortality). Patients who received a PPM were further stratified by weekend hospital admission. Results: Heart block occurred in 200 (38.6%) patients, and atrial arrhythmias with slow ventricular response occurred in 239 (46.1%) patients. Reversible causes of bradycardia included medication toxicity in 22 (4.2%) patients and hyperkalemia in 44 (8.5%) patients. Adverse events were similar in patients who underwent early compared to delayed PPM implantation (6.6% vs 12.5%, P=.20), whereas adverse events were higher in patients who received temporary transvenous pacing (19.1% vs 3.4%, P<.001). Weekend admissions were associated with increased temporary transvenous pacing, prolonged median time to PPM implantation by 1 day, and prolonged median length of stay by 2 days. Conclusions: Delayed PPM implantation was not associated with an increase in adverse events. Weekend PPM implantation should be considered to reduce temporary transvenous pacing and shorten length of stay.