title: Ablation of perimitral flutter following catheter ablation of atrial fibrillation: impact on outcomes from a randomized study (PROPOSE).
abstract: BACKGROUND
  Patients with previous ablation for atrial fibrillation (AF) may experience recurrence of perimitral flutter (PMFL). These arrhythmias are usually triggered from sources that may also induce AF. This study aims at determining whether ablation of triggers or completing mitral valve isthmus (MVI) block prevents more arrhythmia recurrences.
  
  
  RESULTS
  Sixty-five patients with recurrent PMFL after initial ablation of long standing persistent AF were included in this study. Thirty-two patients were randomized to MVI ablation only (Group 1) and 33 were randomized to cardioversion and repeat pulmonary vein (PV) isolation plus ablation of non-PV triggers (Group 2). MVI bidirectional block was achieved in all but 1 patient from Group 1. In Group 2, reconnection of 17 PVs was detected in 14 patients (42%). With isoproterenol challenge, 44 non-PV trigger sites were identified in 28 patients (85%, 1.57 sites per patient). At 18-month follow-up, 27 patients (84%) from Group 1 had recurrent atrial tachyarrhythmias, of whom 15 remained on antiarrhythmic drug (AAD); however, 28 patients from Group 2 (85%, P < 0.0001 vs Group 1) were free from arrhythmia off AAD. The ablation strategy used in Group 2 was associated with a lower risk of recurrence (hazard ratio = 0.10, 95% CI 0.04-0.28, P < 0.001) and an improved arrhythmia-free survival (log rank P < 0.0001).
  
  
  CONCLUSIONS
  In patients presenting with PMFL after ablation for longstanding persistent AF, MVI block had limited impact on arrhythmia recurrence. On the other hand, elimination of all PV and non-PV triggers achieved higher freedom from atrial arrhythmias at follow-up.
authors.affiliation: Texas Cardiac Arrhythmia Institute at St. David's Medical Center, Austin, Texas 78705, USA.
authors.forename: Rong
authors.initials: R
authors.lastname: Bai
authors.forename: Luigi
authors.initials: L
authors.lastname: Di Biase
authors.forename: Prasant
authors.initials: P
authors.lastname: Mohanty
authors.forename: Antonio
authors.initials: A
authors.lastname: Dello Russo
authors.forename: Michela
authors.initials: M
authors.lastname: Casella
authors.forename: Gemma
authors.initials: G
authors.lastname: Pelargonio
authors.forename: Sakis
authors.initials: S
authors.lastname: Themistoclakis
authors.forename: Sanghamitra
authors.initials: S
authors.lastname: Mohanty
authors.forename: Claude S
authors.initials: CS
authors.lastname: Elayi
authors.forename: Javier
authors.initials: J
authors.lastname: Sanchez
authors.forename: J David
authors.initials: JD
authors.lastname: Burkhardt
authors.forename: Rodney
authors.initials: R
authors.lastname: Horton
authors.forename: G Joseph
authors.initials: GJ
authors.lastname: Gallinghouse
authors.forename: Shane M
authors.initials: SM
authors.lastname: Bailey
authors.forename: Aldo
authors.initials: A
authors.lastname: Bonso
authors.forename: Salwa
authors.initials: S
authors.lastname: Beheiry
authors.forename: Richard H
authors.initials: RH
authors.lastname: Hongo
authors.forename: Antonio
authors.initials: A
authors.lastname: Raviele
authors.forename: Claudio
authors.initials: C
authors.lastname: Tondo
authors.forename: Andrea
authors.initials: A
authors.lastname: Natale
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000503:physiopathology / Q000601:surgery*; D001282:Atrial Flutter / Q000209:etiology / Q000503:physiopathology / Q000601:surgery*; D017115:Catheter Ablation / Q000009:adverse effects / Q000379:methods*; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000502:physiology / Q000601:surgery*; D055502:Secondary Prevention; D016896:Treatment Outcome