9-08: Comparison of trans-esophageal echocardiography and FDG PET/CT in the diagnosis of implanted device lead endocarditis

Abstract

18-fluorodeoxyglucose positron emission tomography/computerized tomography (FDG PET/CT) scan has been proposed as a diagnostic tool for cardiac implantable electronic device (CIED) infection. We investigated the role of FDG PET/CT for the diagnosis of lead endocarditis as compared to conventional trans-esophageal echocardiography (TEE). Patients with a confirmed diagnosis of lead endocarditis (positive lead culture after extraction of the suspected CIED) were included in the study. A TEE and a FDG PET/CT scan were performed before extraction and each analyzed blindly to assess for the presence of a lead infection (vegetation and FDG uptake along the device leads). 41 consecutive pts (73 +13 years, 36 male) were studied. At the time of imaging 59% of pts were on antibiotics. TEE identified a lead vegetation in 12 pts (29%); they ranged 2 to 20 mm in size. On FDG PET/CT there was increased uptake along the lead in 33 pts (80%), and along the intra-cardiac portion of the device in 22 pts (54%). Of the 22 patients with a positive intra-cardiac portion on PET/CT, 16 (73%) did not demonstrate a vegetation on TEE. On PET/CT there was increased uptake along the extra-cardiac portion of the lead in 30 pts (73%). When used together, TEE or FDG PET/CT scan identified 38 pts (93%) with lead endocarditis With PET/CT septic emboli were identified in 9 pts (22%): 4 with spondylodiscitis, 4 with septic pulmonary emboli and 1 with an infected vascular prosthesis. Compared to PET/CT, TEE is less sensitive in detecting implanted lead endocarditis. However TEE is necessary for the vegetation size. When used synergistically with TEE it confers higher sensitivity of detecting lead infections, including extra-cardiac involvement (Figure Presented).