title: Lessons from individualized cryoballoon sizing. Is there a role for the small balloon?
abstract: BACKGROUND
  Cryoablation for paroxysmal atrial fibrillation (PAF) is well established. The single-big-balloon strategy has been preferred for pulmonary vein isolation (PVI) using the second generation cryoballoon (CBG2). Individual PV-morphologies raise the question if an individualized anatomic approach using the 23-mm or 28-mm CB is reasonable.
  
  
  METHODS
  Consecutive patients were prospectively enrolled in the non-randomized single-center study. Patients were treated with the 28-mm CB, if any PV was >21mm, the 23-mm CB, if all PV were ≤21mm, or both sizes, if PVI was difficult. The primary endpoint was arrhythmia-free survival. The secondary endpoint considered procedural results and complications.
  
  
  RESULTS
  Overall, 197 patients with symptomatic PAF (64±11 years, 36% female) were included. Acute PVI was achieved in 99.9% of PV. Based on preprocedural imaging, the 28-mm CB was applied as the primary catheter in 47% (92/197 patients), the 23-mm CB in 53% (105/197, p=0.23). The 23-mm CB group included more females, patients with short left atrial (LA)-diameters (each p<0.01), and smaller patients (p=0.04). Both CB-sizes were used in 24% (47/197). Additional 23-mm CB usage was necessary in 23% (21/92) of patients, mainly because of insufficient PV-occlusion with the 28-mm CB. Additional 28-mm CB usage was necessary in 25% (26/105, p=0.82), mainly because PV diameters were larger than initially measured. Both CB-sizes were equally safe and effective with a low complication rate and an overall success rate of 86% at 12 and 71% at 18 months (6% on antiarrhythmic drugs). No predictors for AF-recurrence were identified.
  
  
  CONCLUSIONS
  CB ablation can sometimes be challenging. The 28-mm CB is the preferred catheter in all patients. If balloon positioning is difficult, the 23-mm CB is an option to achieve PVI in small veins. Further studies need to investigate if the 23-mm CB could be beneficial as the primary CB in females with small body height and short LA diameter.
authors.affiliation: Department of Cardiology and Internal Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich Municipal Hospital Group, Munich, Germany. Electronic address: st.hartl1@gmail.com.
authors.forename: Stefan
authors.initials: S
authors.lastname: Hartl
authors.affiliation: Department of Cardiology and Internal Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich Municipal Hospital Group, Munich, Germany.
authors.forename: Uwe
authors.initials: U
authors.lastname: Dorwarth
authors.affiliation: Department of Cardiology and Internal Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich Municipal Hospital Group, Munich, Germany.
authors.forename: Benedikt
authors.initials: B
authors.lastname: Bunz
authors.affiliation: Department of Cardiology and Internal Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich Municipal Hospital Group, Munich, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Wankerl
authors.affiliation: Department of Cardiology and Internal Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich Municipal Hospital Group, Munich, Germany.
authors.forename: Ullrich
authors.initials: U
authors.lastname: Ebersberger
authors.affiliation: Department of Cardiology and Internal Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich Municipal Hospital Group, Munich, Germany.
authors.forename: Ellen
authors.initials: E
authors.lastname: Hoffmann
authors.affiliation: Department of Cardiology and Internal Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich Municipal Hospital Group, Munich, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Straube
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000601:surgery*; D003452:Cryosurgery / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000601:surgery*; D016896:Treatment Outcome
keywords: Ablation; Atrial fibrillation; Cryoballoon; Pulmonary vein isolation; paroxysmal atrial fibrillation