Cardiac amyloidosis is a cause of restrictive cardiomyopathy with preserved ejection fraction associated with amyloid fibrils deposits in the myocardium. Two types of amyloid commonly infiltrate the heart: immunoglobulin light-chain amyloid (AL), and transthyretin-related amyloid amyloidosis (ATTR). Cardiac imaging is currently used for the diagnosis of ATTR, including planar scintigraphy with bone seeking radiopharmaceuticals, cardiac magnetic resonance and echocardiography with global longitudinal strain assessment.Although semi-quantitative methods have been suggested to evaluate the amyloid burden, there a need for quantitative methods for longitudinal assessment of the disease.
Recently, treatment with tafamidis in patients with cardiac ATTR lead to a significant reduction in mortality. The Perugini score is commonly used on planar bone scans to differentiate cardiac ATTR from other amyloidosis or normal patients but fails to evaluate amyloid burden and patient prognosis. Although semi-quantitative methods have been suggested to evaluate the amyloid burden, there a need for quantitative methods for longitudinal assessment of the disease.