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Published on: June 4, 2020
Useful indices of thrombogenesis in the exclusion of intra-cardiac thrombus
Uzoma N Ibebuogu1,2, Joseph H Schafer1, Mark J Schwade1
1Division of Cardiology, Department of Medicine, Augusta University Medical Center, Augusta, GA, USA.
Insights
Supplementing transesophageal echocardiography (TEE) with noninvasive markers like D-dimer can improve the detection of cardiac thrombi in atrial fibrillation patients. This approach offers valuable diagnostic information beyond TEE alone, aiding clinical management.
Area of Science:
- Cardiology
- Diagnostic Imaging
- Biochemistry
Background:
- Cardioversion for atrial fibrillation (AF) poses a risk of cardioembolic stroke.
- Transesophageal echocardiography (TEE) is the standard for diagnosing cardiac thrombi, but its negative results do not entirely rule out thrombus presence.
- Effective clinical management is crucial to mitigate stroke morbidity and mortality in AF patients.
Purpose of the Study:
- To evaluate the diagnostic utility of combining TEE with noninvasive markers for detecting intra-cardiac thrombi.
- To assess if additional noninvasive tests can enhance the accuracy of thrombus absence determination after a negative TEE.
- To improve the diagnostic confidence in identifying patients at risk for cardioembolic events.
Main Methods:
- A prospective study involving 59 patients undergoing TEE for suspected intra-cardiac thrombi.
- Assessment of D-dimer levels and white blood cell counts in conjunction with TEE.
- Analysis of left atrial appendage (LAA) velocity and left ventricular ejection fraction (LVEF) in relation to thrombus presence.
Main Results:
- A negative D-dimer level (<200 ng/mL) effectively excluded intra-cardiac thrombi.
- Patients with thrombi showed significantly reduced LAA velocity and LVEF.
- Biochemical markers (neutrophil, lymphocyte percentages, monocyte counts) were altered in patients with thrombi.
- Combined clinical and biochemical data yielded a larger area under the ROC curve for thrombus diagnostics than individual parameters.
Conclusions:
- Supplementing TEE with LAA velocity, noninvasive LVEF, D-dimer, and hemostatic markers provides valuable diagnostic information.
- This combined approach enhances the assessment for intra-cardiac thrombi.
- Larger studies are warranted to validate the efficacy of this enhanced diagnostic strategy.
Background:
Cardioversion in patients with atrial fibrillation (AF) can cause cardioembolic stroke, and effective clinical management is necessary to reduce morbidity and mortality. Currently, transesophageal echocardiography (TEE) is the accepted standard to diagnose cardiogenic thromboemboli; however, a negative TEE does not eliminate the possibility of left atrial thrombus. The objective of this study was to evaluate the diagnostic value of supplementing the TEE with additional noninvasive markers to ensure thrombus absence.
Methods:
A prospective study was conducted on 59 patients who underwent TEE for suspected intra-cardiac thrombi. The TEE indications included acute ischemic stroke (45.7%) and AF or flutter (59.3%). D-dimer level and white blood cell counts were assessed.
Results:
A negative D-dimer level (<200 ng/mL) excluded the presence of intra-cardiac thrombi. Groups with either negative (n = 14) or positive (n = 45) D-dimer levels had comparable clinical characteristics. Comparing positive D-dimer-level patients with thrombus (n = 7) and without thrombus (n = 33), patients with thrombus had reduced left atrial appendage (LAA) velocity (P = .0024), reduced left ventricular ejection fraction (LVEF) (P = .0263), increased neutrophil percent (P = .0261), decreased lymphocyte percent (P = .0216), and increased monocyte counts (P = .0220). The area under the receiver operating characteristic (ROC) curve for thrombus diagnostics was larger for combinations of clinical and biochemical data than for each parameter individually.
Conclusions:
Supplementing the gold standard TEE with the analysis of LAA velocity, noninvasive LVEF, D-dimer, and hemostatic markers provided additional useful diagnostic information. Larger studies are needed to further validate the efficacy of supplementing the TEE to better assess patients for intra-cardiac thrombi.
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