Usefulness of a multidetector-row computed tomography scanner for detecting pannus formation

Abstract Background Prosthetic valve dysfunction (PVD) as a result of pannus or thrombus formation is an infrequent but serious complication. Currently available diagnostic tools, however, are insufficient to detect a minute pannus and thrombi. The use of a more advanced diagnostic image, multidetector-row computed tomography scanner, may enable us to determine the anatomic and functional causes of PVD. Methods Patients who underwent aortic valve replacement with a St. Jude Medical valve were examined by transthoracic echocardiography and cineradiography to diagnose PVD. Sixteen patients with PVD (PVD group) and 12 patients with normal prosthetic valve function (control group) were studied using the multidetector-row computed tomography scanner. The multidetector-row computed tomography findings in 2 patients with PVD were validated by the observations during reoperation. Results In 13 of 16 patients (81%) in the PVD group and 3 of 12 patients (25%) in the control group, multidetector-row computed tomography demonstrated that an abnormal small tissue, regarded as pannus, was found to extend from the left ventricular septum into the pivot guard. These findings were confirmed by the observations during reoperation in 2 patients in the PVD group. Conclusions Multidetector-row computed tomography can be a useful diagnostic technique for anatomic and functional evaluation of PVD as a result of pannus formation.