Background and purpose: Patent foramen ovale (PFO) is a frequent finding in young patients with stroke. The aim of this study was to assess whether PFO is a family trait.
Methods: Sixty-two consecutive patients younger than 60 years of age with ischemic stroke and 62 age and gender-matched control siblings were examined by means of contrast transcranial Doppler (TCD) of the middle cerebral artery, using a standardized protocol. The reliability of TCD examination in our laboratory was assessed against transesophageal echocardiography (TEE). All TCD recordings were reviewed by a blinded experienced observer from another center. Disagreements between readers were resolved by unblinded consensus review.
Results: Siblings of patients with PFO had a significantly higher prevalence of PFO than had siblings of patients without PFO (61.5% versus 30.6%; OR 3.64 [1.3 to 10.5]; P=0.015). The kappa statistics indicated that agreement of pairs (patients/control siblings) was not due to chance. The strength of the association was sex dependent. In women pairs, prevalence of a PFO was 76.5% in siblings of patients with PFO and 25% in siblings of patients without PFO, giving an OR of 9.8 (95% CI 2 to 47.9; P<0.01). In contrast, in men, no significant difference was observed in the prevalence of PFO between siblings of patients with or without PFO (respectively 33.3% and 35%), giving an OR of 0.9 (95% CI 0.2 to 4.9; P=0.9).
Conclusions: This study suggests that, in women, PFO is a family trait.