RT Journal Article SR Electronic T1 Global and Regional Variations in Transthyretin Cardiac Amyloidosis: A Comparison of Longitudinal Strain and 99mTc-Pyrophosphate Imaging JF Journal of Nuclear Medicine Technology JO J. Nucl. Med. Technol. FD Society of Nuclear Medicine SP 30 OP 37 DO 10.2967/jnmt.120.261893 VO 50 IS 1 A1 Lee, Christopher A1 Chao, Chieh-Ju A1 Agasthi, Pradyumna A1 Seri, Amith R. A1 Shere, Amar A1 Mi, Lanyu A1 Brown, Lisa A1 Marostica, Chance A1 Barry, Timothy A1 Yang, Ming A1 Rosenthal, Julie A1 Unzek, Samuel A1 Mookadam, Farouk A1 Arsanjani, Reza YR 2022 UL http://tech.snmjournals.org/content/50/1/30.abstract AB There are limited data on the head-to-head comparison of 99mTc-pyrophosphate (99mTc-PYP) and echocardiographic strain imaging in the assessment of transthyretin (TTR) cardiac amyloidosis. Methods: At Mayo Clinic Arizona, patients who had undergone both a 99mTc-PYP scan and a transthoracic echocardiogram within a 90-d period were retrospectively identified for chart review and strain imaging analysis. Patients were divided into 2 groups according to their 99mTc-PYP results (PYP-positive [PYP+] or PYP-negative [PYP−]) for the comparison. A standard 17-segment model was used for segmental, regional, and global longitudinal strain comparison. A P value of less than 0.05 was deemed significant. Results: In total, 64 patients were included, the mean age was 75.1 ± 13.0 y, and 57 (89.1%) were male. Comparing the PYP+ to the PYP− group, the left ventricular global longitudinal strain was significantly worse in the former (PYP+ vs. PYP−, −10.5 ± 2.6 vs. −13.1 ± 4.1; P = 0.003). PYP+ patients also had worse regional basal strain (−4.6 ± 2.6 vs. −8.8 ± 4.0, P < 0.001) and a trend toward worse midventricular strain (−9.6 ± 4.0 vs. −11.7 ± 4.4, P = 0.07), but there was no statistical difference in the apical region (−17.6 ± 4.73 vs. −19.0 ± 6.46, P = 0.35). This is consistent with an apex-sparing pattern shown by the relative apical longitudinal strain index (1.3 ± 0.5 vs. 1.0 ± 0.3, P = 0.008). Segment-to-segment analysis demonstrated a significant difference in strain between PYP+ and PYP− segments in 4 segments: basal inferior (P = 0.006), basal anterolateral (P = 0.01), apical septal (P = 0.002), and apical inferior (P = 0.001). Left ventricular diastolic dysfunction was significantly different, with 17 (77.3%) patients in the PYP+ group versus 15 (36.6%) in PYP− participants (P = 0.002). Conclusion: Our study suggested that 99mTc-PYP uptake is related to overall worse LV segmental, regional, and global longitudinal strain function, as well as diastolic function, compared with patients without 99mTc-PYP uptake. These data are important for helping clinicians learn about the echocardiographic function features related to 99mTc-PYP uptake and can help generate hypotheses for future studies.