Diagnostic accuracy of two-dimensional and three-dimensional transesophageal echocardiography in detecting pannus and thrombus in left mechanical valve obstruction

The aim of this study was to determine the accuracy of two-dimensional and three-dimensional transesophageal echocardiography (TEE) in the detection of pannus and thrombus in left mechanical valve obstruction (LMVO) compared with surgical and histopathology findings. Patients with suspected LMVO on transthoracic echocardiography were enrolled consecutively. All patients underwent two-dimensional and three-dimensional TEE, and open-heart surgery to replace obstructed valves. Macroscopic and microscopic analysis of the excised masses was used as the gold standard for the diagnosis of thrombus and/or pannus. Forty-eight patients [34 women (70.8%), age 49±13 years, New York Heart Association II: 68.8%, New York Heart Association III: 31.2%] were enrolled. In the diagnostic of thrombus, the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of three-dimensional TEE were 89.2, 72.7, 85.4, 91.7, and 66.7%, respectively, compared with those of two-dimensional TEE (42.2, 66.7, 43.8, 95, and 7.1%, respectively). In the diagnosis of pannus, the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of three-dimensional TEE were 53.3, 100, 85.4, 100, and 82.5%, respectively; compared with those of two-dimensional TEE (7.4, 90.5, 43.8, 50, and 43.2%, respectively). Receiver operating characteristic curves depict that the area under the curves of three-dimensional TEE was higher than the area under the curves of two-dimensional TEE in both diagnoses of thrombus and pannus (0.8560 vs. 0.7330, =0.0427 and 0.8077 vs. 0.5484, =0.005, respectively). This study indicated that three-dimensional TEE had a higher diagnostic value than two-dimensional TEE in the detection of thrombus and pannus in patients with LMVO, and can be a reliable imaging modality to identify the causes of LMVO.