Distribution of artificial cerebral microemboli in stroke patients with patent foramen ovale

OBJECTIVES: Patent foramen ovale (PFO) is considered as an important risk factor for cerebrovascular diseases. Nevertheless, the relationship between the distribution of high-intensity transient signals (HITS), resulting from injection of air mixed with saline and detected by transcranial Doppler (TCD), and clinical cerebrovascular syndromes in these patients has not been investigated. METHODS: Using TCD, we screened 40 patients with stroke or transient ischemic attack (TIA), in whom PFO was proven by transesophageal echocariography (TEE). Of these, 30 patients (75%) with artificially produced HITS either in the middle cerebral artery (MCA) or the basilar artery (BA) were included in the analysis. RESULTS: Nineteen patients had a stroke or TIA in the carotid territory and 11 patients in the vertebro-basilar territory. HITS were found in the MCA in all 30 patients and in 21 of the 30 patients in the BA. Of the latter, ten patients were in the carotid group and 11 patients were in the veretebro-basilar group, p = 0.011. CONCLUSION: There is a significant association between the distribution of artificial HITS and the clinical cerebrovascular syndromes.