title: Intracardiac echo-facilitated 3D electroanatomical mapping of ventricular arrhythmias from the papillary muscles: assessing the 'fourth dimension' during ablation.
abstract: OBJECTIVE
  Ventricular arrhythmias (VA) originating from a papillary muscle (PM) have recently been described as a distinct clinical entity with peculiar features that make its treatment with catheter ablation challenging. Here, we report our experience using an intracardiac echo-facilitated 3D electroanatomical mapping approach in a case series of patients undergoing ablation for PM VA.
  
  
  RESULTS
  Sixteen patients who underwent catheter ablation for ventricular tachycardia (VT) or symptomatic premature ventricular contractions originating from left ventricular PMs were included in the study. A total of 24 procedures (mean 1.5 per patient) were performed: 15 using a retrograde aortic approach and 9 using a transseptal approach. Integrated intracardiac ultrasound for 3D electroanatomical mapping was used in 15 of the 24 procedures. The posteromedial PM was the most frequent culprit for the clinical arrhythmia, and the body was the part of the PM most likely to be the successful site for ablation. The site of ablation was identified based on the best pace map matching the clinical arrhythmia and the site of earliest the activation. At a mean follow-up of 10.5 ± 7 months, only two patients had recurrent arrhythmias following a repeat ablation procedure.
  
  
  CONCLUSIONS
  An echo-facilitated 3D electroanatomical mapping allows for real-time creation of precise geometries of cardiac chambers and endocavitary structures. This is useful during procedures such as catheter ablation of VAs originating from PMs, which require detailed representation of anatomical landmarks. Routine adoption of this technique should be considered to improve outcomes of PM VA ablation.
authors.affiliation: McGill University Health Center, Montreal, QC, Canada.|Cardiology Department, Luigi Sacco Hospital, Milan, Italy.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Proietti
authors.affiliation: Cardiology Division, Instituto Cardiovascular de Buenos Aires, Buenos Aires, Argentina.
authors.forename: Santiago
authors.initials: S
authors.lastname: Rivera
authors.affiliation: Cardiology Division, Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Canada.
authors.forename: Charles
authors.initials: C
authors.lastname: Dussault
authors.affiliation: McGill University Health Center, Montreal, QC, Canada.|Hôpital Sacré-Coeur de Montréal, Montreal, QC, Canada.
authors.forename: Vidal
authors.initials: V
authors.lastname: Essebag
authors.affiliation: McGill University Health Center, Montreal, QC, Canada.
authors.forename: Martin L
authors.initials: ML
authors.lastname: Bernier
authors.affiliation: Cardiology Division, Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Canada.
authors.forename: Felix
authors.initials: F
authors.lastname: Ayala-Paredes
authors.affiliation: Cardiology Division, Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Canada.
authors.forename: Mariano
authors.initials: M
authors.lastname: Badra-Verdu
authors.affiliation: Cardiology Division, Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Canada jean-francois.roux@usherbrooke.ca.|CHUS - Hôpital Fleurimont, 3001, 12e Avenue Nord, Sherbrooke, QC, Canada J1H N4.
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Roux
mesh_terms: D000200:Action Potentials; D000368:Aged; D000369:Aged, 80 and over; D002304:Cardiac Pacing, Artificial; D017115:Catheter Ablation; D004452:Echocardiography; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006339:Heart Rate; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D010210:Papillary Muscles / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery*; D011237:Predictive Value of Tests; D011792:Quebec; D012008:Recurrence; D012086:Reoperation; D012189:Retrospective Studies; D017180:Tachycardia, Ventricular / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery*; D013997:Time Factors; D016896:Treatment Outcome; D018879:Ventricular Premature Complexes / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery*
keywords: 3D electroanatomical mapping; Catheter ablation; Intracardiac ultrasound; Papillary muscles; Premature ventricular contraction; Ventricular tachycardia