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Efficacy of anticoagulation in resolving left atrial and left atrial appendage thrombi: A transesophageal
W A Jaber1, D L Prior, M Thamilarasan
1Cleveland Clinic Foundation, Cleveland, OH 44195, USA.
Insights
Transesophageal echocardiography (TEE) identified left atrial appendage (LAA) thrombi in 1.9% of patients. Short-term anticoagulation effectively resolved thrombi in 80.1%, but follow-up TEE remains necessary.
Area of Science:
- Cardiology
- Medical Imaging
Background:
- Transesophageal echocardiography (TEE) is the standard for detecting left atrial and left atrial appendage (LAA) thrombi.
- The efficacy of anticoagulation in resolving these thrombi is not fully understood.
Purpose of the Study:
- To determine the incidence and characteristics of left atrial cavity (LAC) and LAA thrombi.
- To evaluate the effectiveness of anticoagulation in thrombus resolution.
Main Methods:
- A retrospective analysis of 9058 TEE studies was conducted.
- Patients with LAC and/or LAA thrombi were identified and their characteristics analyzed.
- Outcomes of anticoagulation therapy were assessed via follow-up TEE.
Main Results:
- 174 patients (1.9%) had LAC or LAA thrombi; LAA thrombi were 6.6 times more common than LAC thrombi.
- LAC thrombi were associated with mitral valve pathology; LAA thrombi were linked to atrial fibrillation/flutter.
- 80.1% of patients achieved thrombus resolution with approximately 47 days of anticoagulation.
Conclusions:
- LAC thrombi are rare, often linked to mitral valve disease, and detectable by transthoracic echocardiography.
- LAA thrombi predominantly occur in patients with atrial fibrillation/flutter.
- Short-term anticoagulation effectively resolves most thrombi but necessitates follow-up TEE.
Background:
Transesophageal echocardiography (TEE) is the gold standard for evaluation of the left atrium and the left atrial appendage (LAA) for the presence of thrombi. Anticoagulation is conventionally used for patients with atrial fibrillation to prevent embolization of atrial thrombi. The mechanism of benefit and effectiveness of thrombi resolution with anticoagulation is not well defined.
Methods And Results:
We used a TEE database of 9058 consecutive studies performed between January 1996 and November 1998 to identify all patients with thrombi reported in the left atrium and/or LAA. One hundred seventy-four patients with thrombi in the left atrial cavity (LAC) and LAA were identified (1.9% of transesophageal studies performed). The incidence of LAA thrombi was 6.6 times higher than LAC thrombi (151 vs 23, respectively). Almost all LAC thrombi were visualized on transthoracic echocardiography (90.5%). Mitral valve pathology was associated with LAC location of thrombi (P <.0001), whereas atrial fibrillation or flutter was present in most patients with LAA location of thrombi. Anticoagulation of 47 +/- 18 days was associated with thrombus resolution in 80.1% of the patients on follow-up TEE. Further anticoagulation resulted in limited additional benefit.
Conclusions:
LAC thrombi are rare and are usually associated with mitral valve pathology. Transthoracic echocardiography is effective in identifying these thrombi. LAA thrombi occur predominantly in patients with atrial fibrillation or flutter. Short-term anticoagulation achieves a high rate of resolution of LAA and LAC thrombi but does not obviate the need for follow-up TEE.
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