[Patent foramen ovale and paradoxical embolism: a controversial hypothesis].

Twenty-four patients with a patent foramen ovale and unexplained ischemic cerebral events are reported. The conventional factors in favour of paradoxical embolism have been evaluated. Five patients (20.8%) mentioned a Valsalva manoeuver just before the onset of their neurological disorders. Only 2 deep venous thrombosis of the legs, one of which resulting from the ischemic event, could be detected. These results do not confirm the hypothesis of paradoxical embolism and are in disagreement with other recent studies. This discrepancy may be due to the choice of the patients. More stringent echocardiographic criteria should be considered in the future.