How is ATTR amyloidosis diagnosed?
Many tests can help diagnose amyloidosis. A biopsy (the removal of a small piece of tissue) of the affected organ is the most useful test. To take a biopsy from the heart, a small, thin, hollow tube (catheter) is placed into a vein in your neck and then guided into the right side of your heart. A few small pieces of the heart muscle are removed.
A pathologist will examine the tissue with a microscope and perform special tests to identify the exact protein causing the amyloidosis.
A bone scan called a technetium pyrophosphate (TcPYP) scan can detect ATTR in the heart (see video). A positive TcPYP scan, along with blood and urine tests to rule out other forms of amyloidosis, can confirm the diagnosis without the need for a heart biopsy. When ATTR amyloidosis is confirmed, a blood test is used to find out if the ATTR is hereditary or wild-type.
Several other tests may be used to check organ function:
- Blood samples to check the kidneys, heart, and liver.
- An electrocardiogram (EKG) and echocardiogram (ultrasound of the heart) to check the heart.
- An MRI of the heart may also be done.
Family members of someone with hereditary ATTR amyloidosis have a higher risk of also having the condition. Close family members, such as parents, siblings and children have a 50% chance of having the mutation. If you have hereditary ATTR amyloidosis, you should talk to a genetic counselor to learn more about the risk of the condition among other family members and genetic testing.