Transthyretin amyloid cardiomyopathy is caused by the deposition of transthyretin amyloid fibrils in the myocardium. The deposition occurs when wild-type or variant transthyretin becomes unstable and misfolds. Tafamidis binds to transthyretin, preventing tetramer dissociation and amyloidogenesis.
Background—Cardiac transthyretin (ATTR) amyloidosis is a progressive and fatal cardiomyopathy for which several promising therapies are in development. The diagnosis is frequently delayed or missed due to limited specificity of echocardiography and the traditional requirement for histologic confirmation. It has long been recognised that technetium labelled bone scintigraphy tracers can localise to myocardial amyloid deposits and use of this imaging modality for diagnosis of cardiac ATTR amyloidosis has lately been revisited. We conducted a multicentre study to ascertain the diagnostic value of bone scintigraphy in this disease.
Amyloidosis affects millions of people, as a cause of Alzheimer's disease or a complication of dialysis, and also causes rare conditions. The many forms of the disorder have one underlying principle: misfolded proteins. Prompt, correct diagnosis is essential, especially in the inherited forms of amyloidosis. This article reviews the molecular basis of various types of amyloidosis and proposes new ways of treating these disorders.
Hereditary transthyretin amyloidosis is caused by pathogenic single-nucleotide variants in the gene encoding transthyretin (TTR) that induce transthyretin misfolding and systemic deposition of amyloid. Progressive amyloid accumulation leads to multiorgan dysfunction and death. Inotersen, a 2′-O-methoxyethyl–modified antisense oligonucleotide, inhibits hepatic production of transthyretin.