Closure of patent foramen ovale: is the case really closed as well?

Assessment is further complicated by an index event, paradoxical embolism, which is almost never directly observed and usually only inferred. [...]neither whether the event is embolic nor whether other embolic sources are "ruled out" constitute iron-clad facts in clinical practice. In this mini-symposium, Amarenco reports that his group did not find an increased frequency of thrombophilia in patients with presumed paradoxical embolism, nor could they document an increased incidence of Valsalva manoeuvres (p 441 ). [...]local formation of thrombus in an atrial septal aneurysm or in the PFO itself is suggested as an alternative pathomechanism to venous thromboembolism.