The role of transoesophageal echocardiography in diagnosis and management of patients with embolic stroke of undetermined source

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Introduction About 25–30% of the cases of ischemic stroke have no established etiology after standard diagnostic evaluation and are classified as embolic strokes of undetermined source (ESUS). Transoesophageal echocardiography (TOE) may provide additional information in the evaluation of patients with ESUS and change the secondary prevention management. Purpose In this retrospective study we examined the role of TOE in diagnosis and further management of patients with ESUS. Methods Patients with ESUS (18 to 60 years old) with no comorbidities were examined at the echocardiography laboratory of our hospital, from April 2018 until August 2022. All patients were thoroughly assessed with transthoracic echocardiography and had no abnormal findings. Atrial fibrillation was excluded by ambulatory electrocardiography. All patients were examined for presence of patent foramen ovale (PFO), aortic atheromatosis and left atrial appendage thrombus. The size of PFO shunt was classified based on the number of microbubbles seen in the left atrium during the first three cardiac cycles after the infusion of agitated saline. The presence of 1–5 microbubbles was classified as small shunt, 6–25 as moderate and >25 as large. Patients with large shunts and RoPE score >6 were referred to occlusion. Τ - test was used to compare the means of the variables and a p value 0.05 was considered statistically significant. Results In this study, 200 patients with ESUS (134 males), of mean age 52.6 (SD=9.8 ears), were enrolled. In 52 of them TOE determined the etiology of stroke. The presence of PFO was found in 70 (35.0%) patients. Of those, 17 (24.3%) had a small shunt, 20(28.6%) a moderate and 32 (45.7%) had a large shunt and were referred to occlusion. Patients with PFO were younger (mean age 47.2 years, SD 11.2, p<0.001) than those without PFO (mean age 54.8 years, SD 8.6) (Diagram 1). Furthermore, 20 (10.0%) patients were diagnosed with atheromatosis of ascending aorta and aortic arch ≥grade 2. Patients with aortic atheromatosis were older (mean age 58.1 years SD 7.6) than those without atheromatosis (mean age 51.9 years, SD 9.8, p = 0.008) (Diagram 2). Finally, TOE did not reveal left atrial appendage thrombus in any of the examined patients. Conclusion TOE revealed the etiology of stroke in about 25% of our patients, which consequently changed their secondary prevention management.