title: Strategies for phrenic nerve preservation during ablation of inappropriate sinus tachycardia.
abstract: Radiofrequency (RF) ablation can alleviate drug-refractory inappropriate sinus tachycardia (IST). However, phrenic nerve (PN) injury and other complications limit its use.
  
  
  
  The purpose of this study was to characterize the maneuvers used to avoid PN injury and the long-term clinical outcomes.
  
  
  
  The study consisted of a retrospective analysis of consecutive patients who underwent ablation for IST.
  
  
  
  RF ablation was performed on 13 consecutive female patients with drug-refractory IST. Eleven patients exhibited PN capture at desired ablation sites. In 1 patient, PN capture was not continuous throughout the respiratory cycle and ventilation holding sufficed to avoid PN injury. In 10 patients, pericardial access (PA) and balloon insertion was required. Initially (n = 4) a posterior PA was used, which was replaced by an anterior PA in the subsequent 6 cases. PA to optimal balloon positioning time was significantly lower in anterior vs posterior PA (16.3 ± 6 minutes vs 58 ± 21.3 minutes, P = .01), as was fluoroscopy time (15.66 ± 16.72 min vs 35.9 ± 1.8 min, P = .03). RF ablation successfully reduced sinus rate to <90 bpm in 13 of 13 patients. Procedure times and total RF times were not significantly different in anterior vs posterior PA. Major complications occurred in 2 patients, including unremitting pericardial bleeding requiring open-chested repair in 1 patient and sinus pauses mandating pacemaker implantation in the other patient. Long-term symptom control after follow-up of 811 ± 42 days was successful in 84.6%.
  
  
  
  Ventilation holding and/or pericardial balloon insertion are frequently warranted in IST ablation. Anterior PA appears to facilitate the procedure over posterior PA.
authors.affiliation: Methodist DeBakey Heart and Vascular Center and Methodist Hospital Research Institute, Houston Methodist Hospital, Houston, Texas.
authors.forename: Sergio Hugo
authors.initials: SH
authors.lastname: Ibarra-Cortez
authors.affiliation: Methodist DeBakey Heart and Vascular Center and Methodist Hospital Research Institute, Houston Methodist Hospital, Houston, Texas.
authors.forename: Moisés
authors.initials: M
authors.lastname: Rodríguez-Mañero
authors.affiliation: Methodist DeBakey Heart and Vascular Center and Methodist Hospital Research Institute, Houston Methodist Hospital, Houston, Texas.
authors.forename: Bahij
authors.initials: B
authors.lastname: Kreidieh
authors.affiliation: Methodist DeBakey Heart and Vascular Center and Methodist Hospital Research Institute, Houston Methodist Hospital, Houston, Texas.
authors.forename: Paul
authors.initials: P
authors.lastname: Schurmann
authors.affiliation: Methodist DeBakey Heart and Vascular Center and Methodist Hospital Research Institute, Houston Methodist Hospital, Houston, Texas.
authors.forename: Amish S
authors.initials: AS
authors.lastname: Dave
authors.affiliation: Methodist DeBakey Heart and Vascular Center and Methodist Hospital Research Institute, Houston Methodist Hospital, Houston, Texas.
authors.forename: Miguel
authors.initials: M
authors.lastname: Valderrábano
mesh_terms: D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D017115:Catheter Ablation / Q000009:adverse effects / Q000379:methods; D004351:Drug Resistance; D005260:Female; D006801:Humans; D007431:Intraoperative Complications / Q000517:prevention & control*; D008875:Middle Aged; D059351:Organ Sparing Treatments / Q000379:methods; D017063:Outcome Assessment, Health Care; D010496:Pericardium / Q000601:surgery*; D059348:Peripheral Nerve Injuries / Q000517:prevention & control*; D010791:Phrenic Nerve / Q000293:injuries*; D012121:Respiration, Artificial / Q000379:methods; D013616:Tachycardia, Sinus / Q000175:diagnosis / Q000601:surgery
chemical_list: D000889:Anti-Arrhythmia Agents
keywords: Catheter ablation; Inappropriate sinus tachycardia; Phrenic nerve injury