Objective: To compare patent foramen ovale (PFO) detected by transesophageal echocardiography (TEE) between patients with PFO complicated paradoxical cerebral embolism (PCE) and those PFO without symptom.Methods: A total of 132 PFO+PCE patients from our hospital were regarded as PFO+PCE group, another 80 patients with asymptomatic PFO identified by physical examination were collected as asymptomatic PFO group.Both groups received esophageal multi-faceted echocardiography at rest and during Valsalva manoeuvre and right ventricular acoustics angiography.PFO size, shunt degree, presence of atrial septal aneurysm.Eustachian valve and PFO tunnel length were recorded.Results: Compared with asymptomatic PFO group, there were significant rise in PFO size [(1.2±1.2)mm vs.(3.8±1.3)mm], PFO tunnel length [(11.2±5.6) mm vs.(13.0±5.8) mm], proportions of large shunt (2.5% vs.41.7%), atrial septal aneurysm (16.3% vs.47.7%) and Eustachian valve (13.8% vs.46.2%) in PFO+ PCE group, P<0.05 or <0.01.Conclusion: The foramen ovale of PFO+PCE patients is usually bigger, typically complicated with large shunt, atrial septal aneurysm and Eustachian valve, and foramen ovale tunnel is longer.These morphological characteristics may be meaningful for paradoxical cerebral embolism.