title: Prevalence of patent foramen ovale in a consecutive cohort of 261 patients undergoing routine "coronary" 64-multi-detector cardiac computed tomography.
abstract: BACKGROUND
  A patent foramen ovale (PFO) is strongly associated with cryptogenic stroke (CS), neurological and other phenomena. The reported prevalence of PFO varies according to the imaging technique used and population studied.
  
  
  OBJECTIVE
  To measure prospectively, the prevalence of PFO in a cohort of consecutive patients attending for routine "coronary" CT angiography using standard, everyday coronary protocols including low-dose prospective ECG gated studies.
  
  
  METHODS
  Standard coronary imaging protocols were used. PFOs were graded according to the classification of Williamson et al.
  
  
  RESULTS
  261 patients were studied. A PFO was identified in 22.6% (11.5% grade 1 (closed flap), 6.5% grade 2 (open flap) and 4.6% grade 3 (open flap with jet)). A further 6.1% had an atrial septal aneurysm.
  
  
  CONCLUSIONS
  The prevalence of all grades of PFO (22.6%) and open flap PFO (11.1% = grade 2 and 3) with this technique compares with 24.3% by trans-oesophageal echocardiography (TOE) and 14.9% by saline contrast echocardiography (SCE). Further comparative studies are required but we believe an open flap PFO or ASA should be identified and recorded during cardiac CT. This approach may identify those at risk of cryptogenic stroke as well as avoid unnecessary tests in stroke patients.
authors.affiliation: Cardiac Unit, Altnagelvin Hospital, Western HSC Trust, Glenshane Road, Londonderry BT47 6SB, United Kingdom. john.purvis@btinternet.com
authors.forename: John A
authors.initials: JA
authors.lastname: Purvis
authors.forename: David R
authors.initials: DR
authors.lastname: Morgan
authors.forename: Sinead M
authors.initials: SM
authors.lastname: Hughes
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D055424:Cardiac-Gated Imaging Techniques / Q000379:methods*; D003287:Contrast Media; D017023:Coronary Angiography / Q000379:methods*; D004452:Echocardiography; D005260:Female; D054092:Foramen Ovale, Patent / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D006801:Humans; D007472:Iohexol; D007494:Ireland / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011446:Prospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D007472:Iohexol