Incidence of thromboembolism following detection by trans-oesophageal echocardiography of left atrial thrombus

Abstract

Background: Left atrial appendage (LAA) thrombus is an accepted risk factor for ischemic stroke. Following a literature review we were unable to identify a study that determined the incidence of ischemic stroke in patients with a confirmed LAA thrombus. The purpose of this study was to establish the incidence of ischemic stroke in patients with a LAA thrombus confirmed on trans-oesophageal echocardiography (TOE). Method: A ten year retrospective single centre study was conducted for the period March 2005 to February 2014 in St. Vincent's University Hospital, Ireland. All TOE studies performed during this period were reviewed. A chart review was carried out on any patient who had a LAA thrombus, left atrial (LA) thrombus or pre-thrombus state identified. Charts were reviewed for documented neurological deficits consistent with ischemic stroke or transient ischemic attack within six months following TOE study. Results: Overall 1903 TOE studies were reviewed. A total of 67 TOE studies detected a LAA thrombus, LA thrombus or pre-thrombus state. In the days prior to TOE, an ischemic stroke had occurred in two of the patients. Following detection of thrombus or pre-thrombus state on TOE and optimization of oral anti-coagulation (OAC), no patient had an ischemic stroke over the subsequent six months. Conclusion: This is the only study to date that has looked at the incidence of ischemic stroke following a confirmed LAA thrombus, LA thrombus or pre-thrombus state. This single centre study found low stroke rates over a six month follow-up period in patients with a confirmed LAA thrombus, LA thrombus or pre-thrombus state and optimization of OAC. Larger studies would be required to confirm these findings.

Keywords

• Left atrial appendage
• Ischemic stroke
• Atrial fibrillation
• Trans-oesophageal echocardiography
• Thrombus
• Anti-coagulation