Transthyretin amyloidosis (ATTR-CM) occurs when your liver produces faulty transthyretin (TTR) proteins. Clumps of these abnormal proteins (called fibrils) build up in your heart's main pumping chamber. Your left ventricle becomes stiff and weak.

ATTR cardiomyopathy (ATTR-CM).

• Fatigue.
• Leg, ankle, or abdominal swelling.
• Shortness of breath with activity.
• Sudden drop in blood pressure upon standing.
• Trouble breathing when laying down.
• Irregular heart beat (arrhythmia).

Transthyretin amyloid cardiomyopathy (ATTR-CM) is one of the types of systemic amyloidosis in which misfolded transthyretin (TTR) protein gets deposited in the myocardium. Another pertinent etiology of cardiac amyloidosis is due to the deposition of immunoglobulin light-chain (AL) aggregates.

One animal study suggested that high doses of vitamin C may help the body break down amyloid and prevent amyloidosis from worsening.

On average, people with familial ATTR amyloidosis live for 7 to 12 years after they get their diagnosis, according to the Genetic and Rare Diseases Information Center. A study published in the journal Circulation found that people with wild-type ATTR amyloidosis live an average of about 4 years after diagnosis.

Signs and symptoms of amyloidosis may include:

• Severe fatigue and weakness.
• Shortness of breath.
• Numbness, tingling, or pain in the hands or feet.
• Swelling of the ankles and legs.
• Diarrhea, possibly with blood, or constipation.
• An enlarged tongue, which sometimes looks rippled around its edge.

Eating less protein can prevent further kidney damage. Eating less salt, including sodium, may also be necessary. This dietary change can help relieve symptoms like swelling and high blood pressure. Choose low-sodium foods and cook your meals with whole ingredients rather than eating processed foods.

One source suggested that sugary foods, sausage products, and fried foods be avoided, and that consumption of milk fat, processed baked goods, and alcohol be reduced. Women with hATTR amyloidosis should not consume more than 15 g of alcohol per day, and men should not consume more than 30 g.

It is recommended to eat a variety of proteins. Ideally a person's diet is high in lean (chicken/fish) and plant based (nuts/seed/soy/beans/lentils) protein. It is best to limit intake of red meat and avoid processed meats.

Heart complications are the most common cause of death in patients with amyloidosis. The degree to which amyloidosis affects the heart is important in determining your prognosis.

A new medication, tafamidis, was approved in 2018 as the first truly disease-modifying treatment for ATTR cardiac amyloidosis, and more medications have been approved for the neuropathy that often results from this disease. “All of these advancements,” Vaishnav says, “have led to a lot of excitement in the field.”

Overall, people with hATTR amyloidosis live between seven and 12 years after diagnosis. The particular genetic mutation in a person's case of hATTR amyloidosis can either improve or worsen their outcome. For example, only 21 percent of people with the genetic mutation S50R live 10 years or longer after diagnosis.