title: Fluoroscopic position of the second-generation cryoballoon during ablation in the right superior pulmonary vein as a predictor of phrenic nerve injury.
abstract: OBJECTIVE
  Phrenic nerve injury (PNI) is the most frequently observed complication during pulmonary vein isolation procedure using the second-generation cryoballoon (CB). Our objective was to analyse the correlation between the fluoroscopic position of the 28 mm CB during ablation in the right superior pulmonary vein (RSPV) and the occurrence of PNI.
  
  
  RESULTS
  A total of 165 patients having undergone the large 28 mm CB ablation were retrospectively reviewed. Positioning of the CB relative to the cardiac silhouette was classified under fluoroscopic guidance in antero-posterior projection during RSPV ablation. Regarding the lower half of the balloon, CB positioning was defined as follows: (A) completely inside the cardiac shadow; (B1) <1/3 outside the cardiac shadow; and (B2) ≥1/3 outside the cardiac shadow. Phrenic nerve injury occurred in 9.7% (16/165) during ablation in the RSPV. The occurrence of PNI was 0.9, 10.6, and 90.1% in positions A, B1, and B2, respectively (A vs. B1, P = 0.01; B1 vs. B2, P < 0.0001). Among other pre-procedural and procedural variables, the B2 position was the strongest independent determinant for predicting PNI at RSPV (P = 0.001, odds ratio: 119.9; 95% confidence interval: 11.6-1234.7) after multivariable analysis.
  
  
  CONCLUSIONS
  The incidence of PNI at the RSPV significantly increased in case of more distal positioning of the CB relative to the cardiac shadow. This simple and straightforward intra-procedural indicator might prone the operators to attempt occluding the RPSV more proximally in order to avoid PNI.
authors.affiliation: Heart Rhythm Management Center, UZ Brussel-VUB, Laarbeeklaan 101, Brussels 1090, Belgium.
authors.forename: Yukio
authors.initials: Y
authors.lastname: Saitoh
authors.affiliation: Heart Rhythm Management Center, UZ Brussel-VUB, Laarbeeklaan 101, Brussels 1090, Belgium.
authors.forename: Erwin
authors.initials: E
authors.lastname: Ströker
authors.affiliation: Heart Rhythm Management Center, UZ Brussel-VUB, Laarbeeklaan 101, Brussels 1090, Belgium.
authors.forename: Ghazala
authors.initials: G
authors.lastname: Irfan
authors.affiliation: Heart Rhythm Management Center, UZ Brussel-VUB, Laarbeeklaan 101, Brussels 1090, Belgium.
authors.forename: Giacomo
authors.initials: G
authors.lastname: Mugnai
authors.affiliation: Heart Rhythm Management Center, UZ Brussel-VUB, Laarbeeklaan 101, Brussels 1090, Belgium.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Ciconte
authors.affiliation: Heart Rhythm Management Center, UZ Brussel-VUB, Laarbeeklaan 101, Brussels 1090, Belgium.
authors.forename: Burak
authors.initials: B
authors.lastname: Hünük
authors.affiliation: Heart Rhythm Management Center, UZ Brussel-VUB, Laarbeeklaan 101, Brussels 1090, Belgium.
authors.forename: Vedran
authors.initials: V
authors.lastname: Velagić
authors.affiliation: Heart Rhythm Management Center, UZ Brussel-VUB, Laarbeeklaan 101, Brussels 1090, Belgium.
authors.forename: Ingrid
authors.initials: I
authors.lastname: Overeinder
authors.affiliation: Heart Rhythm Management Center, UZ Brussel-VUB, Laarbeeklaan 101, Brussels 1090, Belgium.
authors.forename: Kaoru
authors.initials: K
authors.lastname: Tanaka
authors.affiliation: Heart Rhythm Management Center, UZ Brussel-VUB, Laarbeeklaan 101, Brussels 1090, Belgium.
authors.forename: Pedro
authors.initials: P
authors.lastname: Brugada
authors.affiliation: Heart Rhythm Management Center, UZ Brussel-VUB, Laarbeeklaan 101, Brussels 1090, Belgium.
authors.forename: Carlo
authors.initials: C
authors.lastname: de Asmundis
authors.affiliation: Heart Rhythm Management Center, UZ Brussel-VUB, Laarbeeklaan 101, Brussels 1090, Belgium gbchier@yahoo.it.
authors.forename: Gian-Battista
authors.initials: GB
authors.lastname: Chierchia
mesh_terms: D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000601:surgery*; D001530:Belgium; D017115:Catheter Ablation / Q000009:adverse effects*; D003452:Cryosurgery / Q000009:adverse effects* / Q000379:methods; D005260:Female; D005471:Fluoroscopy / Q000009:adverse effects / Q000379:methods; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D059348:Peripheral Nerve Injuries / Q000453:epidemiology* / Q000209:etiology; D010791:Phrenic Nerve / Q000293:injuries*; D011183:Postoperative Complications / Q000453:epidemiology; D011667:Pulmonary Veins / Q000601:surgery; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D016896:Treatment Outcome
keywords: Ablation; Atrial fibrillation; Cryoballoon; Phrenic nerve injury