Abstract:
Objective: To determine the diagnostic performance of the peripheral blood thrombin-antithrombin complex and D-dimer levels in detection of left atrial thrombus in the patients with mitral stenosis Design: Cross-sectional study Setting: Siriraj Hospital Method: 120 consecutive adult patients with mitral stenosis diagnosed by transthoracic echocardiography from heart clinic and Out-patient Department at Siriraj Hospital were recruited for this study. All patients underwent both transesophageal echocardiography (TEE) and peripheral blood tests for thrombin-antithrombin complex and D-dimer levels. Both tests were performed by independent experienced technicians who were blinded to TEE result which was considered as the gold standard for detection of the left atrial thrombus. Result: The sensitivity and specificity of D-dimer for left atrial thrombus detection at the cut-off point of [is less than or equal to] 500 ng/ml were 80% (95% CI, 76.4% - 83.7%) and 66% (95%CI, 68.7% - 70.3%), whereas the sensitivity and specificity of TAT for left atrial thrombus detection at the cut-off point of [is less than or equal to] 3 microgram/l were 75% (95%CI, 71.1% - 79%) and 60% (95%CI, 55.7% - 64.4%) respectively. The positive and negative predictive values for left atrial thrombus detection of D-dimer at the cut-off point of [is less than or equal to] 500 ng/ml were 32.5% and 94.1% respectively, while those of TAT at the cut-off point of [is less than or equal to] 3 microgram/l were 27.8% and 92.1% respectively. The overall diagnostic performance of D-dimer was significantly better than TAT. Conclusion: D-dimer and TAT could be used as the tool for detection of left atrial thrombus in the patients with mitral stenosis. D-dimer has better diagnostic performance for detection of left atrial thrombus in these patients better than TAT
