Uncertain Clinical Relevance of Serial Bone Scintigraphy Findings in Treated Transthyretin Amyloid Cardiomyopathy
Year: 2025
Type: article
Study design: Observational Study
Abstract: Background Technetium-99m–labeled 3,3-diphosphono-1,2-propanodicarboxylic acid ( Tc-DPD) scintigraphy is a critical part of the validated nonbiopsy diagnostic algorithm for transthyretin amyloid cardiomyopathy (ATTR-CM). With the advent of novel disease-modifying therapies for ATTR-CM, there is intense interest in establishing the utility of DPD scans as an indicator of treatment response. Objectives The authors conducted a retrospective multimodality imaging study to determine the utility of Tc-DPD to track treatment response in ATTR-CM. Methods ATTR-CM patients from the United Kingdom National Amyloidosis Centre who were receiving amyloid-specific disease-modifying therapy (DMT) and underwent pre- and post-treatment Tc-DPD/single-photon emission computed tomography–computed tomography scans were included. Myocardial percentage injected dose (PID), a proposed scintigraphic indicator of cardiac amyloid burden, was measured at baseline and follow-up. Change from baseline in this variable was compared with that of other validated biomarkers of disease severity. Results A total of 66 patients with ATTR-CM who received DMT underwent serial Tc-DPD scans. At follow-up, with a median time between Tc-DPD scans of 27.5 months (Q1-Q3: 21.9-33.1 months), there was a mean reduction from pre-DMT myocardial PID on Tc-DPD scintigraphy of 1.5 ± 1.5%. No statistically significant correlation between the change in PID at follow-up and change in echocardiographic, biochemical, or cardiac magnetic resonance parameters was identified. Discordance in which there was an improvement on follow-up Tc-DPD scintigraphy despite disease progression was observed in 28/66 patients (42.4%). Conclusions Our study indicates a poor correlation between reduction in Tc-DPD uptake at follow-up and numerous established biomarkers of ATTR-CM treatment response. Changes in DPD uptake in ATTR-CM patients receiving DMT should be interpreted with caution.
Source: JACC. Cardiovascular imaging
Authors: Yousuf Razvi, Aldostefano Porcari, David F. Hutt, Jonathan Lazari, Adam Ioannou, Rishi K. Patel, Muhammad Umaid Rauf, Tamer Rezk, Oliver Hague, Stefano Filisetti, Helen J. Lachmann, Ashutosh D. Wechalekar, Aviva Petrie, Carol J. Whelan, Lucia Venneri, Ana Martinez-Naharro, Janet A. Gilbertson, Dorota Rowczenio, William E. Moody, Richard Steeds, Jennifer H. Pinney, Philip N. Hawkins, Marianna Fontana, Julian D. Gillmore
Language: English
Subfield: Internal Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: hybrid
Estimated APC paid: $5,000
OpenAlex ID: W4412196705