Application of 99Tc m-pyrophosphate in transthyretin cardiac amyloidosis / 中华核医学与分子影像杂志

ABSTRACT

Objective:To evaluate the diagnostic value of 99Tc m-pyrophosphate (PYP) in transthyretin cardiac amyloidosis. Methods:From December 2018 to July 2019, 17 patients (9 males, 8 females, age (53.4±13.0) years) with suspected cardiac amyloidosis underwent 99Tc m-PYP imaging in Peking Union Medical College Hospital were prospectively included. Visual score and semi-quantitative values (heart to contralateral ratio, H/CL) of 99Tc m-PYP uptake were used to diagnose transthyretin amyloidosis (ATTR). Biopsies and genetic measurements were also developed to evaluate the diagnostic value of the imaging. Results:Five of the 17 patients were diagnosed as ATTR with a visual score of 2-3, H/CL≥1.5, and confirmed with the biopsy or gene test. Four patients were diagnosed as ATTR with positive genetic results but no cardiac symptoms, and their visual scores were between 0 and 1 with H/CL<1.5. Considering the young age of the patients, amyloid deposition might have not yet caused visceral damage. Visual score of other 8 patients with negative 99Tc m-PYP imaging were also between 0 and 1 with H/CL<1.5, 2 of 8 were confirmed with light chain amyloidosis (AL) by biopsy, 3 were clinically diagnosed as AL and 3 were ATTR excluded. The accuracy of 99Tc m-PYP imaging for diagnosing ATTR was 11/11. Conclusion:99Tc m-PYP imaging is helpful for non-invasive diagnosis of transthyretin cardiac amyloidosis.