title: Choice and Utility of Pacing Maneuver in Establishing the Mechanism of Supraventricular Tachycardia: A Single Center Experience.
abstract: BACKGROUND
  To evaluate the choice and utility of pacing maneuvers in the electrophysiology (EP) laboratory in establishing supraventricular tachycardia (SVT) mechanism.
  
  
  METHODS
  We retrospectively examined a cohort of 160 consecutive patients with SVT presenting for invasive EP evaluation to a single center with 8 electrophysiologists. We analyzed the utility of the two most commonly used pacing maneuvers: (1) ventricular entrainment (VE) and (2) His-refractory premature ventricular stimuli (HRPVC) during SVT.
  
  
  RESULTS
  VE was performed in 96 patients: atrial tachycardia (AT) 12, atrioventricular nodal reentrant tachycardia (AVNRT) 66, and orthodromic reciprocating tachycardia (ORT) 18. During VE, AT patients were most likely to have ventriculo-atrial (VA) dissociation (AT 58%, AVNRT 18%, ORT 0%, P < 0.001) and had a tendency towards less SVT termination (AT 0%, AVNRT 9%, ORT 11%, P = 0.19). HRPVCs were delivered in 39 patients: AT 1, AVNRT 24, and ORT 14. Advancement of atrial signal with HRPVC was only observed in ORT (AT 0%, AVNRT 0%, ORT 79%, P < 0.001) and SVT termination was also mostly observed in ORT (AT 0%, AVNRT 4%, ORT 21%, P = 0.33). The overall diagnostic utility of VE was lowest in AT (AT 42%, AVNRT 71%, ORT 83%, P = 0.04), while HRPVC was rarely used in AT. Furthermore, the utilization of maneuvers varied extensively (0% to100%) among the 8 electrophysiologists.
  
  
  CONCLUSIONS
  There is great variation in the utilization of pacing maneuvers and their utility in ascertaining the mechanism of SVT. Our results support the fact that discerning AT from AVNRT mechanism remains the most challenging task in SVT diagnosis.
authors.affiliation: Department of Internal Medicine, University of Pittsburgh Medical Center, USA.
authors.forename: Saddam
authors.initials: S
authors.lastname: Abisse
authors.affiliation: Cardiac Electrophysiology Section, University of Pittsburgh Medical Center, USA.
authors.forename: Evan
authors.initials: E
authors.lastname: Adelstein
authors.affiliation: Cardiac Electrophysiology Section, University of Pittsburgh Medical Center, USA.
authors.forename: Sandeep
authors.initials: S
authors.lastname: Jain
authors.affiliation: Cardiac Electrophysiology Section, University of Pittsburgh Medical Center, USA.
authors.forename: Samir
authors.initials: S
authors.lastname: Saba
keywords: Diagnosis; Mechanism; Pacing maneuvers; Supraventricular tachycardia