title: Epicardial phrenic nerve displacement during catheter ablation of atrial and ventricular arrhythmias: procedural experience and outcomes.
abstract: BACKGROUND
  Arrhythmia origin in close proximity to the phrenic nerve (PN) can hinder successful catheter ablation. We describe our approach with epicardial PN displacement in such instances.
  
  
  RESULTS
  PN displacement via percutaneous pericardial access was attempted in 13 patients (age 49±16 years, 9 females) with either atrial tachycardia (6 patients) or atrial fibrillation triggered from a superior vena cava focus (1 patient) adjacent to the right PN or epicardial ventricular tachycardia origin adjacent to the left PN (6 patients). An epicardially placed steerable sheath/4 mm-catheter combination (5 patients) or a vascular or an esophageal balloon (8 patients) was ultimately successful. Balloon placement was often difficult requiring manipulation via a steerable sheath. In 2 ventricular tachycardia cases, absence of PN capture was achieved only once the balloon was directly over the ablation catheter. In 3 atrial tachycardia patients, PN displacement was not possible with a balloon; however, a steerable sheath/catheter combination was ultimately successful. PN displacement allowed acute abolishment of all targeted arrhythmias. No PN injury occurred acutely or in follow up. Two patients developed acute complications (pleuro-pericardial fistula 1 and pericardial bleeding 1). Survival free of target arrhythmia was achieved in all atrial tachycardia patients; however, a nontargeted ventricular tachycardia recurred in 1 patient at a median of 13 months' follow up.
  
  
  CONCLUSIONS
  Arrhythmias originating in close proximity to the PN can be targeted successfully with PN displacement with an epicardially placed steerable sheath/catheter combination, or balloon, but this strategy can be difficult to implement. Better tools for phrenic nerve protection are desirable.
authors.affiliation: From the Arrhythmia Service, Cardiovascular Division, Brigham and Women's Hospital, Boston, MA.
authors.forename: Saurabh
authors.initials: S
authors.lastname: Kumar
authors.affiliation: From the Arrhythmia Service, Cardiovascular Division, Brigham and Women's Hospital, Boston, MA.
authors.forename: Chirag R
authors.initials: CR
authors.lastname: Barbhaiya
authors.affiliation: From the Arrhythmia Service, Cardiovascular Division, Brigham and Women's Hospital, Boston, MA.
authors.forename: Samuel H
authors.initials: SH
authors.lastname: Baldinger
authors.affiliation: From the Arrhythmia Service, Cardiovascular Division, Brigham and Women's Hospital, Boston, MA.
authors.forename: Bruce A
authors.initials: BA
authors.lastname: Koplan
authors.affiliation: From the Arrhythmia Service, Cardiovascular Division, Brigham and Women's Hospital, Boston, MA.
authors.forename: Melanie
authors.initials: M
authors.lastname: Maytin
authors.affiliation: From the Arrhythmia Service, Cardiovascular Division, Brigham and Women's Hospital, Boston, MA.
authors.forename: Laurence M
authors.initials: LM
authors.lastname: Epstein
authors.affiliation: From the Arrhythmia Service, Cardiovascular Division, Brigham and Women's Hospital, Boston, MA.
authors.forename: Roy M
authors.initials: RM
authors.lastname: John
authors.affiliation: From the Arrhythmia Service, Cardiovascular Division, Brigham and Women's Hospital, Boston, MA.
authors.forename: Gregory F
authors.initials: GF
authors.lastname: Michaud
authors.affiliation: From the Arrhythmia Service, Cardiovascular Division, Brigham and Women's Hospital, Boston, MA.
authors.forename: Usha B
authors.initials: UB
authors.lastname: Tedrow
authors.affiliation: From the Arrhythmia Service, Cardiovascular Division, Brigham and Women's Hospital, Boston, MA. wstevenson@partners.org.
authors.forename: William G
authors.initials: WG
authors.lastname: Stevenson
mesh_terms: D000328:Adult; D017115:Catheter Ablation / Q000379:methods*; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007431:Intraoperative Complications; D008297:Male; D008875:Middle Aged; D010496:Pericardium / Q000294:innervation*; D010791:Phrenic Nerve / Q000293:injuries*; D012189:Retrospective Studies; D013612:Tachycardia, Ectopic Atrial / Q000503:physiopathology / Q000601:surgery*; D017180:Tachycardia, Ventricular / Q000503:physiopathology / Q000601:surgery*
keywords: atrial fibrillation; atrial tachycardia; catheter ablation; phrenic nerve; phrenic nerve injury; phrenic nerve protection; ventricular tachycardia