Pyrophosphate Scintigraphy Changes After Tafamidis Therapy　- Proposed Novel Index From Quantitative Single-Photon Emission Computed Tomography.

BACKGROUND

Because a disease-modifying therapy is now available, bone scintigraphy plays a crucial role in diagnosing transthyretin cardiac amyloidosis (ATTR-CM).

METHODS AND

RESULTS

We retrospectively analyzed 24 patients with ATTR-CM to determine the amyloid accumulation volume (AAV: mean standardized uptake value×volume) of the left ventricular wall. AAV showed a significant decrease (591.1±426.0 vs. 213.8±201.9, P<0.0001) after tafamidis treatment, and correlated with troponin T (R=0.49, P=0.022).

CONCLUSIONS

AAV provided a precise quantitative evaluation of the amyloid burden in ATTR-CM.