Cardiac amyloidosis is a rare disease characterized by the abnormal collection of a protein called amyloid in the heart. Currently, there is no cure for the disease, but there are treatments that aim to address underlying problems and improve quality of life. Factors such as early detection and diagnosis may help improve treatment outcomes. New treatments are also being explored for each of the types of amyloid buildup that may affect the heart. These new treatments are increasing the likelihood of a better prognosis for those with cardiac amyloidosis.

Challenges To Finding a Cure

It has been difficult to find effective treatments and potential cures for cardiac amyloidosis for several reasons.

Cardiac amyloidosis is very rare, likely affecting fewer than 4,000 people every year in the United States. Because the condition is so rare, it is difficult to examine, as there are fewer diagnosed people to participate in clinical trials.

Symptoms of cardiac amyloidosis — shortness of breath, fatigue, swelling, and thickened heart tissue (known as restrictive cardiomyopathy or “stiff heart syndrome”) — are general and tend to mimic those of heart failure. The overlapping symptoms make amyloidosis more difficult to diagnose correctly. Recent research has led scientists to believe that nonspecific cases of heart failure throughout history may have been caused by cardiac amyloidosis. To distinguish cardiac amyloidosis symptoms from general heart failure, doctors must be well aware of the possibility of amyloidosis and then must test with a biopsy to confirm amyloidosis.

Treating Cardiac Amyloidosis

Although there is currently no cure, the landscape of treatments has improved greatly over the past decade. With more people being diagnosed, better therapeutic options have also increased the chances of survival.

The approach to treating cardiac amyloidosis depends on the forms of amyloidosis affecting the heart. Two main types of amyloidosis are responsible for 95 percent of cardiac amyloidosis:

• Amyloid light-chain amyloidosis, or AL amyloidosis
• Transthyretin amyloidosis, or ATTR amyloidosis

AL and ATTR amyloidosis have different root causes, so they are treated and managed slightly differently. However, all treatment aims to slow the production of amyloids and address heart damage.

Important treatment for any type of cardiac amyloidosis is also volume management or getting rid of excess fluid in the body. With cardiac amyloidosis, the heart grows stiff and has trouble pumping fluids. Blood pressure in the heart usually builds up, which then causes fluid to leak out into other parts of the body like the lungs. Diuretics, which are medications that help the body to expel extra fluids, are usually prescribed to help manage fluid leakage from the heart.

Treating AL Amyloidosis

AL amyloidosis is the most common type of amyloidosis in the United States and it can affect the heart, leading to cardiac amyloidosis. In people with AL amyloidosis, their plasma cells (a type of white blood cell in the bone marrow) produce too much of an antibody protein called immunoglobulin light chain. Overproduction of these proteins causes them to clump together and form amyloid deposits or fibrils, which may damage affected organs.

AL amyloid deposits in the heart may cause arrhythmias, or abnormal heartbeats, and even heart failure. These are serious conditions that need to be treated quickly. Damage to the heart is often difficult to treat and may be irreversible, but early detection and diagnosis of cardiac AL amyloidosis can increase the chances of successful treatment.

There are several options for treating AL amyloidosis, including medications and stem cell transplantation. The cause of AL amyloidosis is abnormal plasma cells, so treatments aim to kill and slow the growth of those cells.

Medication

Cardiac AL amyloidosis may be treated with different types of medications including chemotherapy and immunomodulators. In some cases, combinations of different medications may prove to be the most beneficial.

In 2021, the United States Food and Drug Administration (FDA) approved a drug to treat people newly diagnosed with AL amyloidosis: Darzalex Faspro (daratumumab plus hyaluronidase), used in combination with bortezomib, cyclophosphamide, and dexamethasone.

Other medications used to treat cardiac AL amyloidosis include the following:

• Drugs typically used to treat cancer — chemotherapy medications — have also shown to be effective in targeting the plasma cells that cause AL amyloidosis.
• Proteasome inhibitors, which target abnormal cell growth, may be prescribed for AL amyloidosis.
• Immunomodulators aim to starve abnormal cells and also strengthen the immune system so that it can better fight off abnormal cells.

To increase the efficacy of treatment, these drugs are usually given in combination with a steroid such as dexamethasone. Some of these drugs are still investigational for AL amyloidosis and should not be used outside of a sponsored clinical trial. Talk to your health care provider or team about the best course of drug treatment if you have cardiac AL amyloidosis.

Stem Cell Transplantation

Autologous stem cell transplantation is another type of therapy to treat AL amyloidosis. An autologous stem cell transplant, or bone marrow transplant, is a procedure in which healthy cells are removed from your body before you undergo chemotherapy (often the drug melphalan, in the case of AL amyloidosis). After chemotherapy, the healthy stem cells are infused back into your body to help replace the damaged cells.

This treatment targets the root cause of abnormal protein production and may provide more long-term disease improvement. Although a stem cell transplant is generally considered the preferred therapy, only a minority of people with AL amyloidosis are considered eligible for the procedure — for all others, drug treatment is often a better option.

Treating Transthyretin Amyloidosis

Transthyretin amyloidosis (ATTR) can be hereditary or wild-type, depending on whether it's caused by a genetic mutation. Cardiac ATTR results when the amyloid deposits are located in the heart and interfere with normal cardiac function.

In the past, ATTR was considered untreatable, but there have been major recent therapeutic breakthroughs that provide options for people with ATTR. As with AL amyloidosis, treatment options for ATTR aim to improve damage to the heart and address amyloid abnormalities.

Medication To Address Heart Damage

Heart disease and heart failure should be managed carefully, as the usual medications for these conditions in people without amyloidosis (including beta-blockers, ACE inhibitors, and calcium channel blockers) can be harmful to people with ATTR. Talk to your doctor about which medications will be most helpful and effective for addressing heart damage resulting from ATTR amyloidosis.

Medication To Address Amyloid Production

Two medications, Tegsedi (inotersen) and Onpattro (patisiran), were approved by the FDA for hereditary ATTR in 2018. In 2019, the drug tafamidis, also known by brand Vydamax and Vyndaqel, became the first FDA-approved drug for hereditary and wild-type cardiac ATTR. Tafamidis has been shown to slow the progression of ATTR and reduce the risk of cardiac-related hospitalization and death in people with ATTR.

Liver Transplantation

Because most ATTR amyloidosis is caused by the production of amyloid deposits in the liver, liver transplantation may also be helpful to reduce or stop amyloid production.

Important Considerations for Treatment and Symptom Management

In treating and managing the symptoms of cardiac amyloidosis, early detection, diagnosis, and treatment of the condition are important for maximizing the effectiveness of treatment and improving outcomes. Although the condition is severe, new treatments are improving the quality of life and survival in people with cardiac amyloidosis.

Another important consideration for treatment is your team of health care providers. You will want to assemble a team of doctors who have experience treating amyloidosis, including cardiologists, rheumatologists, neurologists. You may also want to seek a referral to a high-volume amyloidosis treatment center.

Talk With Others Who Understand

Talking with other people who understand the disease can be helpful in coping with an amyloidosis diagnosis. MyAmyloidosisTeam is the social network for people with amyloidosis and their loved ones. On MyAmyloidosisTeam, members come together to ask questions, give advice, and share their stories with others who understand life with amyloidosis.

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