Technological Improvements in Cardiac Thrombus Diagnosis

Detection of LV apical thrombus by three-dimensional transesophageal echocardiography

INTRODUCTION

Patients with apical myocardial infarction are at higher risk of developing left ventricular (LV) thrombi. Standard transesophageal echocardiography (TEE) is commonly used in assessing cardiac source of embolic cerebrovascular accident (CVA). Contrast-enhanced transthoracic echocardiography (TTE) improves sensitivity for thrombus detection compared with noncontrast TTE, and however for LV apical thrombi, contrast-enhanced magnetic resonance imaging (MRI) and/or contrast-enhanced computed tomography (CT) outperform both TTE and TEE in some studies.

CASE

A 67-year-old man with history of prior myocardial infarction (MI), four-vessel coronary artery bypass surgery, congestive heart failure with LV ejection fraction of 30%, and diabetes mellitus presented to our facility with acute right occipital-parietal stroke and recent history of left lower extremity ischemia. Head and neck MRI and MR angiography found multiple posterior circulation infarcts suggestive of cardio-embolic etiology. TTE image quality was suboptimal even after contrast use to evaluate for LV thrombus, and due to renal insufficiency, MRI or CT was precluded and 3DTEE identified large LV apical thrombus with mobile components.

CONCLUSION

3DTEE may increase the detection of LV apical thrombi as well as evaluating its characteristics by live imaging as well as by offline reconstruction. TEE may be a useful diagnostic modality, especially in patients with decreased renal function, where iodinated contrast for cardiac CT or Gadolinium for MRI may be contraindicated. Multimodality imaging studies may further prove the utility of 3D echocardiographic imaging in the detection of LV apical thrombus.

Role of Imaging for Suspected Cardiac Thrombus

PURPOSE OF REVIEW

Cardiac thrombus formation is a frequent complication of a variety of prevalent diseases. Embolism of cardiac thrombus has the potential to result in significant morbidity and mortality from cerebrovascular and peripheral vascular events.

RECENT FINDINGS

Echocardiography is the most commonly used imaging modality for diagnosing intracardiac thrombus. However, technological advances in computed tomography and magnetic resonance imaging have allowed newer noninvasive modalities to evolve into robust tools for the clinical evaluation of patients suspected of disease. Complimentary use of these imaging techniques is crucial in the diagnosis of cardiac thrombus and initiation of anticoagulation therapy.