经食道超声心动图评估房间隔水平右向左分流量：一项回顾性研究

A retrospective study was conducted on 186 patients admitted to our hospital from February 2020 to February 2022 with unexplained cerebral infarction, transient ischemic attack (TIA), and migraine, who were confirmed to have a patent foramen ovale (PFO) through transesophageal echocardiography or cardiac catheterization. Both transthoracic echocardiography (cTTE) and transesophageal echocardiography (cTEE) were performed. In addition, during cTEE, the operator clenched their fist and placed it on the patient's abdomen, applying pressure and then releasing it, while the patient performed a Valsalva maneuver. The number of microbubbles appearing in the left atrium and left ventricle within three cardiac cycles was observed to assess the degree of right-to-left shunting at the level of the interatrial septum.