title: Femoral venous pressure waveform as indicator of phrenic nerve injury in the setting of second-generation cryoballoon ablation.
abstract: OBJECTIVE
  Femoral venous pressure waveform (VPW) analysis has been recently described as a novel method to assess phrenic nerve function during atrial fibrillation ablation procedures by means of the cryoballoon technique. In this study, we sought to evaluate the feasibility and effectiveness of this technique, with respect to the incidence of phrenic nerve injury (PNI), in comparison with the traditional abdominal palpation technique alone.
  
  
  METHODS
  Consecutive patients undergoing second-generation cryoballoon ablation (CB-A) from June 2014 to June 2015 were retrospectively analyzed. Diagnosis of PNI was made if any reduced motility or paralysis of the hemidiaphragm was detected on fluoroscopy.
  
  
  RESULTS
  During the study period, a total of 350 consecutive patients (man 67%, age 57.2 ± 12.9 years) were enrolled (200 using traditional phrenic nerve assessment and 150 using VPW monitoring). The incidence of PNI in the overall population was 8.0% (28/350); of these, eight were impending PNI (2.3%), 14 transient (4.0%), and six persistent (1.7%). Patients having undergone CB-A with traditional assessment experienced 18 phrenic nerve palsies (9.0%) vs two in 'VPW monitoring' group (1.3%; P = 0.002). Specifically, the former presented 12 transient (6.0%) and six persistent (3.0%) phrenic nerve palsies, and the latter exhibited two transient (1.3%; P = 0.03) and no persistent (0%; P = 0.04) phrenic nerve palsies.
  
  
  CONCLUSIONS
  In conclusion, this novel method assessing the VPW for predicting PNI is inexpensive, easily available, with reproducible measurements, and appears to be more effective than traditional assessment methods.
authors.affiliation: aHeart Rhythm Management Center bDepartment of Anaesthesiology, UZ Brussel-VUB, Brussels, Belgium *Giacomo Mugnaia and Carlo de Asmundis contributed as first author.
authors.forename: Giacomo
authors.initials: G
authors.lastname: Mugnai
authors.forename: Carlo
authors.initials: C
authors.lastname: de Asmundis
authors.forename: Erwin
authors.initials: E
authors.lastname: Ströker
authors.forename: Burak
authors.initials: B
authors.lastname: Hünük
authors.forename: Darragh
authors.initials: D
authors.lastname: Moran
authors.forename: Diego
authors.initials: D
authors.lastname: Ruggiero
authors.forename: Valentina
authors.initials: V
authors.lastname: De Regibus
authors.forename: Hugo Enrique
authors.initials: HE
authors.lastname: Coutino-Moreno
authors.forename: Ken
authors.initials: K
authors.lastname: Takarada
authors.forename: Rajin
authors.initials: R
authors.lastname: Choudhury
authors.forename: Jan
authors.initials: J
authors.lastname: Poelaert
authors.forename: Christian
authors.initials: C
authors.lastname: Verborgh
authors.forename: Pedro
authors.initials: P
authors.lastname: Brugada
authors.forename: Gian-Battista
authors.initials: GB
authors.lastname: Chierchia
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D003452:Cryosurgery / Q000009:adverse effects*; D004562:Electrocardiography; D005240:Feasibility Studies; D005260:Female; D005268:Femoral Vein; D006801:Humans; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods*; D010173:Palpation; D059348:Peripheral Nerve Injuries / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control; D010791:Phrenic Nerve / Q000293:injuries*; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D014690:Venous Pressure