Comparison of Magnetic Resonance Imaging and Transesophageal Echocardiography in Detection of Thrombus in the Left Atrial Appendage

• Published in: Stroke Vol. 34; no. 10; pp. 2436 - 2439
• Main Authors: Ohyama, Hideo, Hosomi, Naohisa, Takahashi, Tsutomu, Mizushige, Katsufumi, Osaka, Kunihiko, Kohno, Masakazu, Koziol, James A.
• Format: Journal Article
• Language: English
• Published: Hagerstown, MD Ovid Technologies (Wolters Kluwer Health) 01.10.2003; Lippincott Williams & Wilkins
• Subjects: Aged; Aged, 80 and over; Atrial Appendage; Atrial Appendage - diagnostic imaging; Atrial Appendage - pathology; Atrial Fibrillation; Atrial Fibrillation - complications; Atrial Fibrillation - diagnosis; Atrial Fibrillation - diagnostic imaging; Biological and medical sciences; Cardiac dysrhythmias; Cardiology. Vascular system; Echocardiography, Transesophageal; Female; Heart; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Imaging; Male; Medical sciences; Middle Aged; Predictive Value of Tests; Reproducibility of Results; Secondary Prevention; Stroke; Stroke - etiology; Stroke - prevention & control; Thrombosis; Thrombosis - complications; Thrombosis - diagnosis; Thrombosis - diagnostic imaging; magnetic resonance imaging; stroke, cardioembolic; Arrhythmia; Thrombus; Left auricular appendage; Cardiovascular disease; Vascular disease; Heart disease; Complication; Diagnosis; Cerebrovascular disease; Sonography; Human; Nervous system diseases; Stroke; Echocardiography; Atrial fibrillation; thrombi; Method; Medical screening; Nuclear magnetic resonance imaging; Excitability disorder; Embolism; Cerebral disorder; Central nervous system disease; Medical imagery; Comparative study
• ISSN: 0039-2499; 1524-4628; 1524-4628
• DOI: 10.1161/01.str.0000090350.73614.0f

Background and Purpose— A noninvasive technique of visualizing the left atrial appendage (LAA) and its thrombus in patients with atrial fibrillation would be of great interest. This study examined the utility of MRI for the assessment of thrombus in the LAA. Methods— We evaluated 50 subjects with nonrheumatic continuous atrial fibrillation and a history of cardioembolic stroke. Each patient received an MRI and a transesophageal echocardiography (TEE) on the same day for thrombus detection in the LAA. Both double- and triple-inversion recovery sequences were used for the MRI evaluations. Results— In all subjects, the LAA was readily visualized with MRI. High-intensity masses in the LAA were clearly distinguishable from the LAA wall in the triple–inversion recovery sequences. Concordance between detection of high-intensity mass with MRI and thrombus with TEE was high: no mass (MRI), no thrombus (TEE), 31 patients; mass (MRI), thrombus (TEE), 16 patients; and mass (MRI), no thrombus (TEE), 3 patients (overall κ=0.876, SE=0.068). Conclusions— MRI is a noninvasive and reproducible modality for thrombus detection in the LAA of patients with nonrheumatic continuous atrial fibrillation and previous cardioembolic stroke.