Background: It has been proposed that the patent foramen ovale (PFO) may be associated with migraine, in particular migraine with aura. However, it is not clear whether paradoxical embolism triggers crises of headache. Cerebral embolization is provoked in subjects with PFO through contrast echocardiography, a safe method to diagnose the presence of foramen ovale pervium.
Methods: Twenty-four men practicing diving, an activity characterized by increased prevalence of PFO and migraine, underwent trans-thoracic echocardiography with contrast solution, composed of saline and air mixture and checked for the occurrence of migraine in the following 24 hours.
Results: A PFO (five of minimal size, i.e. visible only during Valsalva, one of small and two of medium size) was detected in 8/24 divers (33%). No one reported headache over the 24 hours after the procedure.
Discussion: Our preliminary data suggest that cerebral micro-embolism, provoked by contrast echocardiography, does not systematically trigger migraine crises when a minimal-to-medium sized patent foramen ovale is present.