OBJECTIVES: The aim of this study was to examine the frequency and causes of surgical explantation of patent foramen ovale (PFO) closure devices. BACKGROUND: PFO has been linked with cryptogenic strokes, recurrent transient neurologic deficits, sleep apnea, decompression illness, and migraines. Several randomized trials are in progress to determine whether PFO closure is preferable to medical management in the treatment of patients with cryptogenic strokes or migraine. The majority of PFO closures are performed off-label, because there is no U.S. Food and Drug Administration approval for use of any device to close a PFO. As data are accumulating on the benefits of implanting PFO closure devices, it is also important to examine complications that might occur. METHODS: We performed a database review to identify the frequency and causes of PFO device explantation, examining 18 PFO closure centers in Europe and the United States. RESULTS: Of the 13,736 percutaneous PFO device implantations performed over the past 9 years at these 18 institutions, 38 devices (0.28% [95% confidence interval: 0.20% to 0.37%]) required surgical removal. There were a wide range of causes cited for these removals. The most common cause for explantation was chest pain (n = 14), often determined to be secondary to nickel allergy to the PFO device. Other causes for explantation included persistence of a residual shunt (n = 12), the presence of thrombus on the device (n = 4), pericardial effusion (n = 2), perforation of the atrium or aortic root (n = 2), recurrent strokes (n = 1), the development of endocarditis (n = 1), and undocumented reasons (n = 2). CONCLUSIONS: The vast majority of PFO closure procedures are performed safely with minimal complications. However, there is a small (0.28%) incidence of severe long-term problems associated with PFO closure that might require surgical removal of the device. In addition, the frequency of surgical explantation was found to be device-dependent; some of these devices seem to be safer than others.