Utility of Transthoracic Echocardiography and Carotid Doppler Ultrasound in Differential Diagnosis and Management of Ischemic Stroke in a Developing Country

Abstract

Objective—We sought to describe findings, diagnostic yield, cost effectiveness of transthoracic echocardiography (TEE) and Carotid doppler ultrasound (CDU) in ischemic stroke. Methods—Cross sectional study at Mulago hospital, Uganda. Institutional ethical approval, patient consent was obtained. Patients eighteen years and above with ischemic stroke confirmed by brain computerized tomography (CT) scan and met inclusion criteria were selected. TTE and CDU were done as part of comprehensive assessment for stroke risk factors. Data was analyzed using SPSS 14. Univariate analysis was done for social-demographics, abnormalities on cardiac imaging and diagnostic yield using TOAST criteria. Bivariate analysis for association between stroke risk factors, cardio-embolic stroke and other ischemic subtypes (diagnosed using clinical and CT scan features). Statistical significance was set at P<0.05. Results—Of 139 screened patients with suspected stroke, 127 underwent brain CT scan as 12 died before CT. Eighty five were confirmed stroke by CT scan with 66 (77.6%) ischemic stroke, mean age 62 years (SD+16.6), 53% were male. Out of 66, 62 (93.9%) underwent both TTE and CDU. Although only 7 (11.3%) reported history of heart disease, 43 (69.3%) had abnormal findings on TTE with left atrial enlargement commonest in 21 (48.8%). Thirty eight (61.3%) had abnormal finding on CDU with atherosclerosis commonest in 28 (45.2%). Using clinical and CT scan features, atherosclerotic stroke was the commonest subtype in 29 (46.8%) then cardio embolic 18 (27.3%). Only 6 (9.7%) patients had abnormal findings on TTE suggesting possible cardio-embolism by TOAST criteria. None had stenosis >50% on CDU. Multiple valvular lesions P<0.001, severe valvular lesions P=0.001 were associated with cardio-embolic stroke. Conclusions—Majority of ischemic stroke patients without previous history of heart disease had abnormal findings on TTE and CDU. Diagnostic yield for cardio-embolic stroke by TOAST criteria was very low given the high cost involved for a developing country.