Cardiac Amyloidosis - XVII
Transthyretin (TTR) Amyloidosis
The precursor fibril protein of senile systemic amyloidosis (SSA) is normal or wild-type transthyretin (TTR), previously known as prealbumin.
TTR is synthesized mainly by the liver and acts as transporter protein for thyroxine and retinol.
The protein consists of 127 amino acids encoded by 4 exons located in chromosome 18. Analysis of the protein in SSA revealed normal TTR with predominantly C-terminal fragments admixed with intact full-length monomers.
Here we show some examples of cardiac amyloidosis caused by transthyretin showing minimal infiltration of the atrial muscle in isolated atrial amyloidosis, as well as heavier infiltration of the atrial endocardium the ventricular myocardium and the vessels and adipose tissue within the heart..