Perspective:

This important study investigated the relationship between PFO and stroke in the general population. While previous case-control studies have demonstrated a relationship between PFO and stroke, this prospective study showed no association between PFO and either clinical stroke or subclinical cerebrovascular disease. This study will provide reassurance to clinicians and patients regarding the incidental finding of PFO, and affirms that there does not appear to be a role for therapies directed at primary prevention of stroke. The age of the patient population was relatively advanced (mean age almost 69 years), and the prevalence of PFO was somewhat smaller than reported in some studies at 14.9%. This may have been due to the use of transthoracic echocardiography for diagnosis of PFO. This study should not impact secondary prevention strategies for patients with previous stroke, as they have self-selected themselves into a high-risk group and therefore cannot be compared with the general population. Importantly, although several high-risk features of PFO have been put forth (size, presence of atrial septal aneurysm), further investigation will be required to prospectively identify individuals with PFO at risk for ischemic stroke.