[Patent foramen ovale--demographic, clinical and echocardiographic characteristics].

Patent foramen ovale (PFO) represents the most common persistent abnormality of fetal origin. The aim of the study was to analyze the incidence and characteristics of PFO and to assess PFO as the risk factor of paradoxical embolism. 945 consecutive pts (442F and 503M aged 13-85, mean 53.02 +/- 14.42 years) in whom TEE was performed and flow through PFO was detected in basal conditions (colour-Doppler) and/or during provocation (Valsalva/cough manoeuvre) with contrast (saline infusion) at the period 1998-2002 was retrospectively analyzed. 183 pt had a history of systemic embolisation (SE) or transient ischemic attack (TIA). PFO was diagnosed [PFO(+)] in 57 pts (6%)-22F, 35M aged 14-77 years, mean 52.44 +/- 14.84 years. 888 pts without PFO [PFO(-)] created a control group. Two subgroups were analyzed in the study group: xPFO(+) - 28 pts with PFO as the only abnormality, yPFO(+) - 29 pts with PFO and other heart/aortic disease. Similarly, in the control group two subgroups were analysed: xPFO(-) - pts with normal TEE and negative history of heart/aortic disease and yPFO(-) - pts without PFO but with other heart/aortic disease. Aneurysmal formation of interatrial septum was detected in 24 pts, and in 6 pts it coexisted with PFO. The intensity of shunt was significantly higher in yPFO(+) than in xPFO(+) group. In 5 pts permanent shunt through PFO at the basal stage was observed (4 pts with significant regurgitation of the atrio-ventricular valves and one patient with tricuspid stenosis). Percentage of pts with the history of SE/TIA was significantly higher in group xPFO(+) than in xPFO(-) (p < 0.01).

CONCLUSIONS

(1) PFO is a risk factor of SE/TIA only in group xPFO(+). (2) Flow through PFO in group xPFO(+) is generally minimal. (3) In case of coexisting heart pathology PFO may provoke significant right-to-left or even left-to-right shunt.