TY - JOUR T1 - Electrocardiogram-Gated <sup>18</sup>F-FDG PET/CT Hybrid Imaging in Patients with Unsatisfactory Response to Cardiac Resynchronization Therapy: Initial Clinical Results JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 67 LP - 71 DO - 10.2967/jnumed.110.078709 VL - 52 IS - 1 AU - Christopher Uebleis AU - Michael Ulbrich AU - Roland Tegtmeyer AU - Franziska Schuessler AU - Nadine Haserueck AU - Johannes Siebermair AU - Christoph Becker AU - Stephan Nekolla AU - Paul Cumming AU - Peter Bartenstein AU - Stefan Kääb AU - Marcus Hacker Y1 - 2011/01/01 UR - http://jnm.snmjournals.org/content/52/1/67.abstract N2 - The present study aimed to distinguish responders to cardiac resynchronization therapy (CRT) from nonresponders, using electrocardiogram-gated 18F-FDG PET/CT. Methods: Seven consecutive CRT nonresponders were included in the study, along with 7 age- and sex-matched CRT responders, serving as reference material. Therapy response was defined as clinical improvement (≥1 New York Heart Association class) and evidence of reverse remodeling. Besides PET/CT, we measured brain natriuretic peptide levels and assessed dyssynchrony using transthoracic echocardiography. Results: Compared with nonresponders, CRT responders showed significant differences in the declines of left-ventricular end-systolic volume and brain natriuretic peptide and in left-ventricular dyssynchrony (global left-ventricular entropy), extent of the myocardial scar burden, and biventricular pacemaker leads positioned within viable myocardial regions. Among the nonresponders, further therapy management was guided by the PET/CT results in 4 of 7 patients. Conclusion: Cardiac hybrid imaging using gated 18F-FDG PET/CT enabled the identification of potential reasons for nonresponse to CRT therapy, which can guide subsequent therapy. ER -