Improved aetiological diagnosis of ischaemic stroke in a Vascular Medicine Unit - The significance of transesophageal echocardiogram

Background: The TOAST study estimates that 34% of ischaemic strokes are of undetermined aetiology. Improvements in the diagnosis of the pathogenetic mechanism of ischaemic stroke would translate into a better care, in analogy to other fields of vascular and internal medicine. Objective: To measure the reduction of undetermined aetiology strokes performing a set of additional diagnostic tests. Design: Consecutive case series with historical controls. Setting: Internal Medicine Ward with a stroke area (SA) admitting most stroke patients of a large hospital in Italy. Subjects: A total of 179 ischaemic stroke patients admitted to SA in 2004-2005 compared with 105 ischaemic stroke patients admitted to the whole department in 2001. Intervention: To perform more diagnostic tests, including transesophageal echocardiography (TEE), in the greatest possible number of ischaemic stroke inpatients admitted in SA of the Internal Medicine Department, in the years 2004-2005. Results: More diagnostic tests were performed during the study period than in 2001, especially TEE (56% of patients in 2004-2005 vs. 3% of patients in 2001). We observed a significant reduction of undetermined aetiology from 38% in 2001 to 16% in 2004-2005 (p <0.0001), largely for an increased identification of cases of cardio-embolic mechanism (from 18% to 40%, p = 0.0002). In the years 2004-2005 the fraction of patients on anticoagulant treatment at discharge was 21% vs. 12% in 2001 (p = 0.041). Conclusion: Performing more tests, particularly TEE, brought improvements in the aetiological diagnosis of stroke, increasing cardio-embolism diagnosis and anticoagulant treatment.