Well there you go an all i will do is to try an humanise the condition after you have read the informed links.
There re 2 types of Amyloid, 1) Primary Amyloid 2) Secondary Amyloid.
I am not going to deal with primary Amyloid as it covered in the NHS websites, except to say that it is autoimmuine disorder,affecting almost all and any organs of the body, rare, but when it presents, it presents as unexplained heart failure.
Secondary Amyloid ( I call it that as it explains the condition) is always secondary to some other disease. It was by far the commonest cause of the "Amyloids" as before antibiotics WW2 and just after, it was commonly encountered wherever there was PUS......osteomyelitis, lung abscess and empyema(pus) of the gall bladder BUT....with the advent of antibiotics, this association became divorced, but still it was linked with other chronic diseases e.g rheumatoid arthritis.
It's treatment is outlined in Buenchico's link, so i will leave it at that.
Life expectancy will depend upon the organs involved, but the prognosis is improving year by year.