ABSTRACT

Bone tracers have been validated for many years in detecting transthyretin cardiac amyloidosis (TTR-CA). However, several new studies suggest conflicting results. Our study aimed to systematically evaluate the accuracy of bone radiotracers for diagnosis and differentiation of TTR-CA via a systematic review and meta-analysis.

We retrieved articles assessing the performance of bone tracer in diagnosing and differentiating TTR-CA from PubMed, the Cochrane Library, ScienceDirect, and DOAJ databases, dating up to 10 July 2020. The meta-analysis was conducted through Stata 16 software, and the risk of bias for the included studies was assessed by the QUADAS-2 tool. Moreover, we made a comprehensive review.

Fourteen articles were included in the systematic review, and 9 in the meta-analysis. The pooled sensitivity was 0.97 (95% confidence interval [95% CI] 0.85–0.99) with heterogeneity (I2=73.5, 95% CI 55.6–91.2), and the specificity was 0.92 (95% CI 0.82–0.96) with heterogeneity (I2=42.0, 95% CI 0.0–86.9). The pooled positive and negative likelihood ratios were 11.49 (95% CI 5.07–26.0) and 0.03 (95% CI 0.01–0.18), respectively. The diagnostic odds ratio was 341 (95% CI 53–2194), and the area under the receiver operating characteristic curve was 0.96 (95% CI 0.94–0.97).

The findings evidence that the bone radiotracer is a valuable noninvasive approach that provides high accuracy for diagnosing TTR-CA and plays a modest role in differentiating TTR-CA from immunoglobulin amyloid light-chain cardiac amyloidosis. 99mTc-HMDP may be more accurate than 99mTc-PYP, 99mTc-DPD, and 18F-NaF in the TTR-CA detecting process, and 18F-NaF is a promising bone tracer to diagnose and differentiate TTR-CA.