Predictive Value of D-dimer Levels for Detection of Left Atrial Thrombus in Patients with Rheumatic Severe Mitral Stenosis

Background: Systemic embolism is one of the most common complications of mitral stenosis (MS). Systemic embolism in patients with MS is caused by left atrial (LA) thrombus. Trans Esophageal Echocardiography (TEE) is considered the most reliable in ruling out LA thrombus, however, it is semi-invasive, operator-dependent, and not widely available. On the other hand, D-dimer is an indirect marker of fibrin formation. It reflects the activation of coagulation system. Objective: To measure D-dimer levels in patients with and without LA thrombus and find out predictive value of D-dimer levels to detect LA thrombus. Methods: In this cross-sectional observational study 50 patients with rheumatic severe mitral stenosis have been assessed. Patients underwent Trans Thoracic Echocardiography (TTE) and TEE to rule out LA thrombus. If TTE showed LA thrombus, TEE was not done. Patients were divided into two groups based on presence of LA thrombus; group I- patients with LA thrombus, and group II- patients without LA thrombus. D-dimer level was measured in two groups and comparison was done. Results: D-dimer was significantly elevated in group I compared to group II (2.8±1.9 µg/ml vs. 0.43±0.13µg/ml, p<0.001). Receiver Operator Characteristic (ROC) Curve showed D-dimer level > 0.6 µg/ml can predict LA thrombus with sensitivity of 84% & specificity of 88%. Conclusion: A higher level of D-dimer can predict LA thrombus in patients with rheumatic severe MS, and can be used as a noninvasive marker to rule out LA thrombus in patients with rheumatic severe MS. Bangladesh Medical Res Counc Bull 2022; 48(3): 231-235