Multicenter Study of Planar Technetium 99m Pyrophosphate Cardiac Imaging

Abstract

In this multicenter study, Tc 99m PYP cardiac imaging conferred a high level of sensitivity and specificity for differentiation of patients with ATTR cardiac amyloidosis (irrespective of genotype) from patients with AL cardiac amyloidosis and patients with nonamyloid heart failure with preserved ejection fraction. An H/CL ratio of 1.6 or greater was associated with worse survival among patients with ATTR cardiac amyloidosis. Among patients for whom there is a high clinical suspicion of cardiac amyloidosis, Tc 99m PYP may be of diagnostic and prognostic importance.

Transthyretin V122I (pV142I)* cardiac amyloidosis: an age-dependent autosomal dominant cardiomyopathy too common to be overlooked as a cause of significant heart disease in elderly African Americans

“…The second US-based multicenter experience with 99m Tc-PYP reported excellent cross-center test validity and prognostic value ascribed to a positive test result (heart-to-contralateral chest ratio >1.6). 55 With a positive scan, subsequent genetic testing showing V122I would therefore confer diagnosis. For these reasons, these scans hold great promise for increasing ATTR recognition without having to resort to endomyocardial biopsy.…”

Clinical Masks of Amyloidosis With the Heart Involvement: Modern Diagnostic Issues

“…Совсем недавно диагностические возможности этого хорошо известного изотопа подтверждены при сравнении 121 больного с ATTR (независимо от генотипа) с 50 боль-ными с не-ATTR амилидозом [18]: чувствительность метода составила 91%, специфичность 92%. Соотно-шение интенсивности сигнала с контрлатеральной стороной ≥1,6 (как это наблюдалось у больной Г.)…”

Transthyretin Cardiac Amyloidosis in Older Adults: Optimizing Cardiac Imaging to the Corresponding Diagnostic and Management Goal

“…Among the non-invasive cardiac imaging modalities studied to-date, nuclear scintigraphy has demonstrated strong evidence for accurate subtyping given the preferential affinity of these agents for TTR amyloid fibrils [33, 45, 46, 49, 51, 52, 65]. In 45 elderly patients with biopsy proven CA (16 ATTRwt, 17 ATTRm, 12 AL, mean ages 77, 70, 63, respectively), a Tc99m-PYP H/CL ratio >1.5 was found to be 97% sensitive and 100% specific for distinguishing ATTR-CA from AL [49].…”