Patent foramen ovale: friend or foe?

Transesophageal echocardiography (TEE) has been increasingly used for the evaluation of patients with a suspected cardiac source of embolization (1). Transesophageal echocardiography findings such as spontaneous echocardiographic contrast, atrial septal aneurysm (ASA), patent foramen ovale (PFO), aortic atheroma, left atrial thrombi, and cardiac masses have been related to an increased risk of embolization (2–8) based on a higher prevalence in patients with suspected embolism compared with those who underwent TEE for other reasons. These findings have also been useful to risk-stratify patients with atrial fibrillation (9,10). In the last 15 years, significant efforts have been made to understand the clinical significance of these findings and to identify the optimal treatment (11–16).