Abstract:Objective To compare the characteristics of transesophageal echocardiography in symptomatic (history of cryptogenic stroke or transient ischemic attack) and asymptomatic patients with patent foramen ovale. Methods Symptomatic patients (with cryptogenic stroke or TIA) with PFO and asymptomatic patients with PFO who were incidentally diagnosed by transesophageal echocardiography were enrolled to this retrospective study in the condition that they were aged younger than 55 years. Not only the clinical and demographic characteristics of 2 groups were compared, but also their morphological features including the length and height of tunnel, atrial septal excursion distance, thickness of septum primum, and thickness of septum secundum. Results The height of PFO (3.0 ±?0.7)?mm VS (2.1?±?0.4)?mm, thickness of septum secundum (6.1?±?1.2)?mm VS (3.4?±?0.9)?mm, and septal excursion distance (8.3?±?1.2) mm VS (4.2?±?1.3) mm, were found to be greater in the symptomatic group than those in the asymptomatic group (P?0.05). There was no significant difference regarding the length of tunnel and thickness of septum primum (P?>?0.05). The ratio of length to height of PFO tunnel was less in the symptomatic group (3.1?±?0.4)?mm VS (5.8?±?1.1)?mm, (P?0.05). Conclusions Our findings appear to indicate that high PFO tunnel, relatively great interatrial septal mobility, thick septum pellucidum may help identifying the risk of cryptogenic stroke or TIA.