title: Outcome predictors of empirical slow pathway modulation: clinical and procedural characteristics and long-term follow-up.
abstract: OBJECTIVE
  Catheter-based modulation of the slow pathway is the first-line therapy of atrioventricular nodal reentrant tachycardia (AVNRT), the most common supraventricular tachycardia (SVT). In patients with a typical history, in whom AVNRT is not inducible during an electrophysiological study, the current guidelines allow consideration of empirical slow pathway modulation (ESPM) under the precondition that both, dual nodal pathway physiology (DNPP) and an ECG documentation compatible with AVNRT exist. This recommendation is based on small series. Furthermore, it is unknown whether ESPM is beneficial in the presence of ECG documentation but the absence of DNPP or vice versa in the presence of DNPP but absence of ECG documentation.
  
  
  METHODS
  Out of 3003 patients who underwent slow pathway modulation from 1993 to 2013, we included 116 patients (68 female; median age 47.0 years) with symptomatic tachycardia who had non-inducible SVT. All patients either had ECG documentation of SVT (66 %) or DNPP (89 %) or both (54 %). All patients underwent ESPM. No severe complications occurred.
  
  
  RESULTS
  After a follow-up time of 64 ± 5.3 months, 81 % of all patients had benefited from ESPM (49 % freedom of symptoms, 32 % improvement). In patients with ECG documentation but absence of DNPP 100 % benefited (85 % freedom of symptoms; 15 % improvement). In patients with DNPP but absence of ECG documentation 75 % benefited (40 % freedom of symptoms, 35 % improvement).
  
  
  CONCLUSIONS
  In a large cohort of patients, ESPM is a safe procedure that improves clinical symptoms in the majority of patients during long-term follow-up. We show for the first time that this also applies for cases where there is no DNPP but a characteristic ECG documentation, and vice versa.
authors.affiliation: Division of Electrophysiology, Department of Cardiovascular Medicine, University Hospital Münster, Münster, Germany. christian.pott@ukmuenster.de.
authors.forename: Christian
authors.initials: C
authors.lastname: Pott
authors.affiliation: Division of Electrophysiology, Department of Cardiovascular Medicine, University Hospital Münster, Münster, Germany.
authors.forename: Felix K
authors.initials: FK
authors.lastname: Wegner
authors.affiliation: Division of Electrophysiology, Department of Cardiovascular Medicine, University Hospital Münster, Münster, Germany.
authors.forename: Nils
authors.initials: N
authors.lastname: Bögeholz
authors.affiliation: Division of Electrophysiology, Department of Cardiovascular Medicine, University Hospital Münster, Münster, Germany.
authors.forename: Gerrit
authors.initials: G
authors.lastname: Frommeyer
authors.affiliation: Division of Electrophysiology, Department of Cardiovascular Medicine, University Hospital Münster, Münster, Germany.
authors.forename: Dirk G
authors.initials: DG
authors.lastname: Dechering
authors.affiliation: Division of Electrophysiology, Department of Cardiovascular Medicine, University Hospital Münster, Münster, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Zellerhoff
authors.affiliation: Division of Electrophysiology, Department of Cardiovascular Medicine, University Hospital Münster, Münster, Germany.
authors.forename: Simon
authors.initials: S
authors.lastname: Kochhäuser
authors.affiliation: Division of Electrophysiology, Department of Cardiovascular Medicine, University Hospital Münster, Münster, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Milberg
authors.affiliation: Division of Electrophysiology, Department of Cardiovascular Medicine, University Hospital Münster, Münster, Germany.
authors.forename: Julia
authors.initials: J
authors.lastname: Köbe
authors.affiliation: Division of Electrophysiology, Department of Cardiovascular Medicine, University Hospital Münster, Münster, Germany.
authors.forename: Kristina
authors.initials: K
authors.lastname: Wasmer
authors.affiliation: Division of Electrophysiology, Department of Cardiovascular Medicine, University Hospital Münster, Münster, Germany.
authors.forename: Günter
authors.initials: G
authors.lastname: Breithardt
authors.affiliation: Division of Electrophysiology, Department of Cardiovascular Medicine, University Hospital Münster, Münster, Germany.
authors.forename: Gerold
authors.initials: G
authors.lastname: Mönnig
authors.affiliation: Division of Electrophysiology, Department of Cardiovascular Medicine, University Hospital Münster, Münster, Germany.
authors.forename: Lars
authors.initials: L
authors.lastname: Eckardt
mesh_terms: D017115:Catheter Ablation / Q000706:statistics & numerical data*; D015897:Comorbidity; D004562:Electrocardiography / Q000706:statistics & numerical data; D005260:Female; D005500:Follow-Up Studies; D005858:Germany / Q000453:epidemiology; D006329:Heart Conduction System / Q000601:surgery*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000175:diagnosis / Q000453:epidemiology* / Q000517:prevention & control; D015995:Prevalence; D011379:Prognosis; D012189:Retrospective Studies; D018570:Risk Assessment; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000175:diagnosis / Q000453:epidemiology* / Q000601:surgery*; D016896:Treatment Outcome
keywords: AV node; AVNRT; Electrophysiology; Empirical slow pathway modulation; Supraventricular Tachycardia