title: The role of the sizing balloon in selection of the patent foramen ovale closure device size.
abstract: OBJECTIVE
  To find a correlation between the patent foramen ovale (PFO) size measured by the sizing balloon and the appropriate closure device size.
  
  
  METHODS
  The PFO of 57 patients was closed using a sizing balloon. A mathematical model was introduced to relate the PFO balloon waist diameter to the closure device size based on the PFO transformation from a slit-like to a circular form during balloon inflation. According to this model, PFOs smaller than 8 mm should be closed with a 25 mm device, PFOs 8 mm to 11 mm with a 35 mm device, and PFOs larger than 11 mm with an Amplatzer septal occluder. In the first group, 36 patients (63.2%) received an appropriately sized device and six patients (10.5%) received an oversized device. In the second group, 15 patients (26.3%) received an undersized device.
  
  
  RESULTS
  A comparison of the PFO dimensions in two views showed that the PFO slit was circular when the balloon was inflated. A six-month echocardiography follow-up was obtained in 46 patients (80.7%). Five patients (13.9%) in the group with an appropriately sized device had a discrete residual shunt during Valsalva. In the second group, five patients (33.3%) had a residual shunt (P = 0.06), of which one was considered large.
  
  
  CONCLUSIONS
  The sizing balloon is helpful in selecting the PFO closure device size. Consequently, the incidence of residual shunt and recurrent events may be reduced.
authors.affiliation: Division of Cardiology, University Hospital of Geneva, Geneva, Switzerland.
authors.forename: J
authors.initials: J
authors.lastname: Alibegovic
authors.forename: Rf
authors.initials: R
authors.lastname: Bonvini
authors.forename: U
authors.initials: U
authors.lastname: Sigwart
authors.forename: Pa
authors.initials: P
authors.lastname: Dorsaz
authors.forename: E
authors.initials: E
authors.lastname: Camenzind
authors.forename: V
authors.initials: V
authors.lastname: Verin