Should we consider patent foramen ovale and secundum atrial septal defect as different steps of a single anatomo-clinical continuum？

1 Introduction Isolated atrial septal defects （ASD） represent 7% of all cardiac anomalies and can present at any age. Adolescents and adults with simple congenital heart disease such as isolated atrial septal defects are more likely to reach adult age without being diagnosed. Secundum ASD （sASD） is by far the most common type, occurring in 1/1500 live births, with 65% to 75% involving females, On the other hand, patent foramen ovale （PFO） represents an endemic variant in the normal population with a prevalence of 25%-27%. These two entities appear so different that is difficult to fred a conjunction ring： nevertheless we use the same philosophy for the treatment, Indeed, device-based closure has been proved to be effective in both settings.