Cerebral embolism with interventional closure of symptomatic patent foramen ovale: an MRI-based study using diffusion-weighted imaging.

Paradoxical embolism via patent foramen ovale (PFO) is an important cause of stroke, especially in younger patients. Transcatheter PFO closure is considered to bear a low risk and to be technically feasable with a high primary success rate. There are no data for the rate of procedure-associated silent embolic events. The present study sought to analyze the total number of cerebral ischemic complications with interventional PFO closure. Thirty-five symptomatic PFO patients (15 male, 26-71 years) with cerebral infarctions proven by magnetic resonance imaging (MRI) were examined by diffusion-weighted imaging (DWI) before and after PFO closure. In the MRI examinations following the intervention, new microembolic lesions were found in three of 35 (8.6%) patients. The lesions were located in the right and left thalamus and the left frontoparietal white matter respectively. Two of three infarcts were clinically inapparent, whereas the third patient suffered from a transient right-sided hemihypaesthesia for 12 h. If the prevention of recurrent cerebrovascular events associated with the presence of PFO is necessary, a low frequency of closure associated silent cerebral embolisms was documented after interventional PFO closure. The rate of microembolic events with neurological deficit was 1/35 (approximately 2.8%).