From the Guidelines
Transesophageal echocardiogram (TEE) is strongly recommended for evaluation of potential left ventricular thrombus after a likely embolic stroke without a clear cause, as it offers superior visualization of cardiac structures and can significantly alter treatment strategy and help prevent recurrent strokes. The most recent and highest quality study, 1, published in 2021, emphasizes the importance of detecting LV thrombus in the context of secondary stroke prevention. According to this study, standard transthoracic echocardiography is relatively insensitive for the detection of LV thrombus, and both contrast echocardiography and cardiac MRI are superior imaging modalities.
The procedure should be performed as soon as clinically feasible after the stroke, ideally within 72 hours if the patient is stable enough to undergo the procedure. TEE requires conscious sedation and involves inserting a probe into the esophagus, which provides clearer images of the left atrium, left atrial appendage, cardiac valves, and left ventricle where thrombi commonly form. Patients should fast for at least 6 hours before the procedure.
Some key points to consider when evaluating the need for a TEE include:
- The detection of LV thrombus would typically lead to anticoagulation therapy, usually with warfarin or a direct oral anticoagulant for at least 3-6 months.
- TEE is particularly important in cryptogenic stroke cases as identifying a cardiac source like LV thrombus can significantly alter treatment strategy and help prevent recurrent strokes.
- The risk of stroke among patients with defined LV thrombus has been reported to be as high as 9% to 11%, emphasizing the need for prompt and accurate diagnosis 1.
- The use of oral anticoagulation with VKA has been shown to reduce the risk of stroke by 86% and result in resolution of LV thrombus in 68% of patients, highlighting the importance of anticoagulation therapy in the management of LV thrombus 1.
Overall, the evidence supports the use of TEE as a valuable tool in the evaluation of potential left ventricular thrombus after a likely embolic stroke without a clear cause, and its use can significantly impact patient outcomes by guiding treatment and preventing recurrent strokes.
From the Research
Level of Recommendation for TEE after Likely Embolic Stroke
- The level of recommendation for a Transesophageal Echocardiogram (TEE) after a likely embolic stroke without a clear cause to evaluate for Left Ventricular (LV) thrombus is supported by several studies 2, 3, 4.
- According to these studies, TEE is a useful tool in identifying potential causes of stroke, including cardioembolic sources such as LV thrombus 2, 4.
- The use of TEE is recommended in patients with suspected cardioembolic stroke, particularly when the cause is unclear 3, 4.
- A dedicated cardiologist experienced in the management of cardioembolism should provide a tailored clinical and echocardiographic assessment, including TEE, if a cardioembolic stroke is suspected 3.
Diagnostic Accuracy of TEE for LV Thrombus
- While TEE is a valuable tool in diagnosing LV thrombus, its diagnostic accuracy is not the highest among imaging modalities 5.
- Cardiac magnetic resonance (CMR) has the highest diagnostic accuracy for LV thrombus, followed by echocardiography with the use of echocardiographic contrast agents (ECAs) 5.
- However, TEE remains a widely available and useful diagnostic tool in the assessment of patients with suspected cardioembolic stroke 2, 4.
Clinical Guidelines and Recommendations
- Current guidelines suggest the use of anticoagulant therapy for at least 3 months in patients with LV thrombus 6, 5.
- The use of TEE in patients with suspected cardioembolic stroke is recommended as part of a comprehensive diagnostic workup 3, 4.
- A national consensus statement recommends that neurologists identify cases that need referral to a cardiologist and that cardiologists provide a tailored clinical and echocardiographic assessment, including TEE, if a cardioembolic stroke is suspected 3.