<i>In vivo</i> quantification of amyloid burden in TTR-related cardiac amyloidosis

Abstract

Cardiac transthyretin-related (ATTR) amyloidosis is a severe cardiomyopathy for which therapeutic approaches are currently under development. Because non-invasive imaging techniques such as cardiac magnetic resonance imaging and echocardiography are non-specific, the diagnosis of ATTR amyloidosis is still based on myocardial biopsy. Thus, diagnosis of ATTR amyloidosis is difficult in patients refusing myocardial biopsy. Furthermore, myocardial biopsy does not allow 3D-mapping and quantification of myocardial ATTR amyloid. In this report we describe a Tc-DPD-based molecular imaging technique for non-invasive single-step diagnosis, three-dimensional mapping and semiquantification of cardiac ATTR amyloidosis in a patient with suspected amyloid heart disease who initially rejected myocardial biopsy. This report underlines the clinical value of SPECT-based nuclear medicine imaging to enable non-invasive diagnosis of cardiac ATTR amyloidosis, particularly in patients rejecting biopsy.

Cardiac transthyretin amyloidosis 99mTc-DPD SPECT correlates with strain echocardiography and biomarkers

“…We do however believe that quantitative DPD SPECT, together with other known biomarkers, has the potential to add new information to the basic understanding of ATTR disease progression, as well as in the understanding of the mechanisms in treatment response. Research of novel treatments are under development [ 11 , 12 ], and new imaging techniques are investigated [ 24 , 34 , 35 , 41 ]. It is plausible that quantitative DPD might have an important role in the evaluation of such treatments.…”

“…Echocardiography and echocardiographic strain analysis are widely studied, important diagnostic and prognostic tools for CA [ 30 – 33 ]. The new treatments have increased demand for imaging techniques that can evaluate the cardiac amyloid burden and function to assess the efficacy of treatment [ 24 , 34 , 35 ]. It is plausible that in addition to echocardiography, quantitative DPD might have an important role in the evaluation of upcoming treatments.…”

Cardiac amyloidosis: a review of the literature and a practical approach for the clinicians

“…Quantification of amyloid load at diagnosis is of prognostic relevance, indicating survival benefit of patients with an amyloid load <20%. [87][88][89][90][91]…”