Learn The BasicsTransthyretin amyloid cardiomyopathy (ATTR-CM) is a rare disease affecting the heart.
Here are some frequently asked questions about ATTR-CM, answers to them, and links to ATTR-CM Companion pages with more information.
What are the symptoms of ATTR-CM?
The symptoms of ATTR-CM are the same as those of congestive heart failure. They include fatigue, swelling in the legs or abdomen, shortness of breath, a sudden drop in blood pressure upon standing, difficulty breathing, feeling faint or lightheaded, and heart arrhythmias. Additionally, some individuals may also experience gastrointestinal problems.
Read more about the symptoms of ATTR-CM
How do doctors diagnose ATTR-CM?
Because ATTR-CM is rare, it is difficult to diagnose. Your doctor may suspect the disease based on your symptoms and medical and family history. They will then conduct some tests to reach a final diagnosis. These may include electrocardiography, echocardiography, cardiac magnetic resonance imaging, bone scintigraphy, heart biopsy and genetic testing.
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What causes ATTR-CM?
ATTR-CM is caused by misfolded transthyretin (TTR) protein accumulating in the heart muscle and other body parts and damaging them.
Read more about the causes and risk factors of ATTR-CM
Does ATTR-CM run in families?
There are two types of ATTR-CM: hereditary ATTR-CM and wild-type ATTR-CM.
Hereditary ATTR-CM develops as the result of a genetic mutation in the gene coding for the TTR protein. This mutation leads to the protein misfolding and forming protein aggregates in the heart muscle and elsewhere. This type of disease does run in families and is inherited in an autosomal dominant manner, meaning that a person with a mutation in the TTR gene has a 50% chance of passing it to their children.
In wild-type ATTR-CM, there is no known mutation in the TTR gene causing the disease. Researchers believe that TTR protein aggregate occurs as a result of the normal aging process. There is no evidence to suggest that this type of disease runs in families.
How common is ATTR-CM?
The exact prevalence of ATTR-CM is not known, but experts believe the disease is significantly underdiagnosed.
Are there any treatments for ATTR-CM?
There is one drug specifically approved by the US Food and Drug Administration for treating ATTR-CM. It is called tafamidis and is sold under the brand name Vyndamax or Vyndaqel. It is a small molecule drug that stabilizes the structure of TTR protein, ensuring it does not form aggregates.
There are also other treatments that doctors may prescribe off-label to treat ATTR-CM, including tolcapone (Tasmar)—a drug normally used to treat Parkinson disease—and diflunisal (Dolobid), which, like tafamidis, work as TTR stabilizers.
Other off-label drugs that may be used to treat ATTR-CM include patisiran (Onpattro), vutrisiran (Amvuttra) and eplontersen (Wainua). These are so-called TTR silencers and inhibit the production of TTR protein.
Medical devices, such as a permanent pacemaker, implantable cardioverter-defibrillator or left ventricular assist device, may be used to assist the heart’s function.
In severe cases, patients may be treated with a heart and/or liver transplantation.
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What is the outlook like for someone with ATTR-CM?
The average life expectancy of a person diagnosed with ATTR-CM can vary between 2 and 6 years from the time of diagnosis.
Read more about the prognosis of ATTR-CM
Can lifestyle changes help me feel better?
Lifestyle changes that can help improve the symptoms of ATTR-CM include keeping a healthy weight, quitting smoking, engaging in moderate physical exercise, getting adequate rest, limiting liquid intake and avoiding or limiting alcohol consumption.
Reviewed by Kyle Habet, M.D., on November 14, 2024.