Can neuroimaging differentiate PFO and AF-related cardioembolic stroke from the other embolic sources? Clinical-radiological correlation on a retrospective study

The aim of this retrospective study was to map the specific ischemic lesion patterns of distribution in patent foramen ovale-related stroke (PFO-stroke) and atrial fibrillation-related stroke (AF-stroke) in patients with idiopatic ischemic stroke. 750 ischaemic strokes were screened on basis of diagnostic imaging and tests: patients with known causes were excluded. 171 patients with unknown cause were selected and divided in two groups: AF-stroke (43 patients) and PFO-stroke (128 patients). Vascular territories of ischemic involvement were divided into four classes in each group: the anterior cerebral artery, the middle cerebral artery, the vertebro-cerebral artery (including the posterior cerebral artery) and multisite (MS) involvement. Infarcts in vertebro-basilar territory and multisite represented each one about 32% of infarcts in PFO-stroke group and their involvement are more frequent than AF-stroke group (p = 0.03). Ischemic lesions in PFO-group were predominantly cortical (34.3%), and in AF-group cortical-subcortical (60.4%). Multisite pattern of ischemic lesion was more frequent in patients with severe degree of right to left shunts (37.5%). In clinical practice, PFO may be considered a cause of cortical stroke on the basis of radiological findings, when VB vascular territory or MS brain involvement is present in younger patients (