2025 Update Consensus of 99mTc-Pyrophosphate Scintigraphy in the Transthyretin Cardiac Amyloidosis from the Taiwan Society of Cardiology and the Society of Nuclear Medicine of the Republic of China.

Abstract

This 2025 updated consensus outlines the diagnostic strategy for transthyretin amyloid cardiomyopathy (ATTR-CM). Given that ATTR-CM is a significant contributor to heart failure, this article emphasizes the importance of making an early and precise diagnosis, particularly as new therapeutic options become available. Highlighting the critical importance of an early and accurate diagnosis, particularly in light of emerging therapeutic modalities, this consensus underscores the central role of ^99mTc-pyrophosphate (PYP) scintigraphy as a non-invasive diagnostic tool. The consensus calls for the adoption of standardized imaging protocols and interpretation criteria to ensure consistency and reliability across diverse clinical settings. The integration of qualitative and quantitative imaging techniques within a structured diagnostic framework places particular focus on the use of single-photon emission computed tomography/computed tomography (SPECT/CT) imaging to enhance diagnostic precision by minimizing blood pool activity and eliminating overlapping interference. Three-hour imaging is considered to be critical for accurate evaluations and to reduce false-positive findings, and it is recommended for its superior diagnostic accuracy. Moreover, quantitative assessments are also considered to be essential for evaluating myocardial amyloid deposition. This updated consensus provides comprehensive guidelines for clinicians, with the aim of optimizing patient outcomes through precise diagnosis and effective management of ATTR-CM. The consensus concludes by advocating for continued research and refinement of imaging methodologies, particularly to enhance the clinical applicability of ^99mTc-PYP scintigraphy and other future developments in nuclear molecular imaging.