Research Article: Can transesophageal echocardiography be safely deferred? A low-cost predictive model using D-dimer to exclude left atrial thrombus in treatment-naïve rheumatic mitral stenosis
Abstract:
Transesophageal echocardiography (TEE) is the reference standard for excluding left atrial thrombus (LAT) in rheumatic severe mitral stenosis (SMS), yet its availability is limited in many low-resource settings. A reliable, low-cost strategy to safely defer TEE would have a significant clinical impact. This study evaluated whether D-dimer–based predictive models can accurately exclude newly detected LAT in treatment-naïve patients with rheumatic SMS.
Sixty-eight consecutive patients with rheumatic SMS who were not receiving anticoagulation underwent D-dimer testing, transthoracic echocardiography, and TEE. Associations with LAT were assessed using conventional and Firth-penalized logistic regression. Diagnostic performance was evaluated using receiver operating characteristic analysis with 1,000-bootstrap internal validation. Two composite models were examined: D-dimer combined with atrial fibrillation (AF) and D-dimer combined with mitral valve area (MVA).
LAT was newly detected in 12 patients (17.6%). D-dimer levels were significantly higher in LAT-positive patients (943.5 vs. 168.5?ng/mL, p <?0.001). The optimal D-dimer cut-off (360.6?ng/mL) achieved 100% sensitivity, 71.4% specificity, and an optimism-corrected AUC of 0.935, outperforming the conventional 500?ng/mL threshold (sensitivity 75%). In adjusted models, D-dimer remained a strong independent predictor of LAT (per SD: AOR 6.91; 95% CI 2.72–17.54). Composite models demonstrated similarly high discrimination (AUC 0.933–0.940); adding AF did not improve performance, whereas incorporating MVA increased specificity to 100%.
D-dimer may help exclude LAT in treatment-naïve patients with rheumatic SMS. Its potential role in supporting more selective TEE use in resource-limited settings warrants further evaluation in larger prospective multicenter studies.
Introduction:
Transesophageal echocardiography (TEE) is the reference standard for excluding left atrial thrombus (LAT) in rheumatic severe mitral stenosis (SMS), yet its availability is limited in many low-resource settings. A reliable, low-cost strategy to safely defer TEE would have a significant clinical impact. This study evaluated whether D-dimer–based predictive models can accurately exclude newly detected LAT in treatment-naïve patients with rheumatic SMS.
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