Size of PFO and amount of microembolic signals in patients with ischaemic stroke or TIA

Abstract

The inter-relation between the size of patent foramen ovale (PFO) by transesophageal echocardiography (TEE) and the amount of microembolic signals (MES) on transcranial doppler (TCD) is still not determined. The study group comprised of 104 patients with first-ever ischaemic stroke or transient ischemic attack (TIA). Three groups were formed according to the amount of MES on TCD: a small amount of MES (0-10 MES); a moderate amount of MES (countable MES higher than 10); and multiple MES. According to TEE, there were 52 patients (50%) with a small PFO, 37 patients (35.6%) with a moderate PFO, and 15 patients (14.4%) with a large PFO. There were 48 patients (46.1%) with a small amount of MES, 34 patients (32.7%) with a moderate amount of MES, and 22 patients (21.1%) with multiple MES on TCD. A strong relationship between the size of the PFO on TEE and the amount of MES on contrast transcranial Doppler was found (P < 0.0001), such that the larger the PFO on TEE, the greater the amount of MES on TCD. There is a high correlation between the size of the PFO on TEE and the amount of MES on TCD in stroke and TIA patients.