Background: Left ventricular assist devices (LVADs) improve quality of life and long-term survival in advanced heart failure, but device related infections (DRI) remain cumbersome. We evaluated the diagnostic capability of FDG-PET/CT and the additive value of semi-quantitative analysis for the diagnosis of DRI.
Methods: LVAD recipients undergoing FDG-PET/CT between December 2012 and August 2020 for suspected DRI were retrospectively included. FDG-PET/CT was performed and evaluated according to EANM guidelines and assessors were blinded to the clinical context of included patients. Final clinical diagnosis of driveline infection and/or central device infection, based on multidisciplinary consensus and findings during surgery whenever performed, was used as the reference for the diagnosis.
Results: 44 patients were evaluated for 62 episodes of suspected DRI. Clinical evaluation established driveline infection in 33 (54%) episodes, central device infection in 8 (14%) and combined infection in 2 (4%). Visual analysis of FDG-PET/CT achieved a sensitivity and specificity of 0.83 and 0.73, respectively, for driveline infections, while semi-quantitative analysis found comparable results (p=0.77). For central device component infections, visual analysis of FDG-PET/CT achieved a sensitivity and specificity of 1.0 and 0.26, respectively, while semi-quantitative analysis using SUVratio (background liver) achieved a sensitivity and specificity of 1.0 and 0.8, respectively. Both SUVmax and SUVratio outperformed visual analysis (p<0.001).
Conclusions: FDG-PET/CT is a valuable tool for the assessment of DRI in LVAD recipients. Semiquantitative analysis significantly increases specificity of FDG-PET/CT for the analysis of central device components and should be considered in equivocal cases after visual analysis.