What is Cardiac Amyloidosis?

The cause of cardiac amyloidosis happens when amyloid build up in the heart tissue. The cardiac amyloid proteins replace normal tissue and stiffen the heart muscle, leading to loss of heart function by decreasing the heart's ability to pump fluid and potentially impacting electrical signaling capabilities. Cardiac amyloidosis can be genetic, develop alongside other diseases, or result from an inflammation-causing medical issue.

Risk Factors for Amyloid Heart Disease

Although the root cause of heart amyloidosis is unknown, there are several risk factors, including:

• Most people diagnosed with amyloidosis are over 40, and those patients diagnosed with ATTR amyloidosis, the most common type, are typically over 70.
• More than three-quarters of people diagnosed with ATTR amyloidosis are men.
• Some forms of amyloidosis are hereditary.
• Patients with amyloidosis often have another chronic disease.

Cardiac amyloidosis symptoms depend on the organ(s) involved and many symptoms are also common for other forms of heart disease.

Patients with cardiac amyloidosis may initially experience the following symptoms:

• Swelling of legs, ankles, or other portion of the body (such as abdominal swelling or enlargement)
• Pressure or dull pain in chest during exertion (similar to what is felt with angina)
• Fatigue, reduced activity tolerance
• Shortness of breath with activity
• Breathing difficulty while lying down

Symptoms often worsen as the diseases progresses.

Before a patient comes for their first appointment, they will be asked to provide a detailed medical history. This will help the Brigham and Women’s team to care for them more efficiently.

During the evaluation appointment, every patient will receive:

• An echocardiogram
• Blood tests
• A 60-90-minute consultation with the program’s lead physician

Some patients will receive:

• A cardiac magnetic resonance imaging (MRI)and/or a nuclear (pyrophosphate) scan of the heart. This is used to produce detailed images of the heart, and a specific imaging agent (gadolinium) is used to help diagnose cardiac amyloidosis
• A skin biopsy if they have suspected light chain amyloidosis. A skin biopsy and blood tests are the first steps to look for an excess of light chains in the blood. A bone marrow biopsy, usually obtained from the hip bone, will identify abnormal cells that are producing the abnormal protein in AL amyloidosis. Depending on these results, a heart, kidney or liver biopsy may be needed
• A cardiac biopsy with advanced tissue-staining techniques to confirm the presence of cardiac amyloidosis and the form of amyloid deposited in the heart
• Genetic testing for patients with ATTR amyloidosis
• Precise assessment of cardiac function by state-of-the-art, noninvasive testing, including echocardiographic strain imaging by speckle tracking and coronary flow reserve by PET scanning, in order to better determine patient eligibility for aggressive therapy
• Evaluation by the Advanced Heart Failure/Cardiomyopathy Program for patients potentially eligible for heart transplantation

View a series of short echocardiography video clips that reveal typical features of cardiac amyloidosis.

Cardiac amyloidosis treatment for each patient will vary according to the type of amyloidosis they have, how far the disease has progressed and the presence of any underlying conditions.

Treatment for Light-Chain Associated (AL) Amyloidosis

AL treatment has advanced considerably over the last 10 years. Treatment will be administered to stop the production of abnormal light chains caused by plasma cells, end the progression of the disease and improve damaged organs.

Although amyloidosis is not a cancer, chemotherapy or chemotherapy-like drugs are used to destroy the abnormal plasma cells. A common combination is a chemotherapy agent cyclophosphamide, with a therapy called bortezomib (Velcade) that specifically targets the plasma cells with a steroid (dexamethasone). This therapy, given once a week either by tablet or injection under the skin, is often referred to as “CyBorD.”

An antibody therapy, daratumumab, has also proven highly effective. Daratumumab may be incorporated with CyBorD from the beginning of therapy or may be added a month or two later. Daratumumab is usually given once a week and is generally well-tolerated.

In general, treatment for AL amyloidosis lasts for 6 to 12 months, but some patients may get ongoing maintenance therapy in the form of pills. Your care team will provide more information on the recommended therapy and what to expect from treatment.

Treatment for Transthyretin-Related Amyloidosis (ATTR)

ATTR treatment can include drugs, therapies and cardiac electrophysiology procedures. When all other measures have proven ineffective, physicians may recommend heart transplantation.

Common ATTR amyloidosis treatment options include:

• The drug Tafamidis, which stabilizes the TTR protein and slows the production of amyloid
• Gene silencers that stop the production of the ATTR protein are approved for patients with familial amyloid polyneuropathy (hereditary form of ATTR that affects the nerves)

Implantable cardioverter defibrillator or a pacemaker may be recommended to treat atrial and ventricular arrhythmias, which sometimes develop as ATTR progresses.The Cardiac Amyloidosis Program coordinates care with non-cardiac specialists for patients with co-existing conditions such as pulmonary hypertension, peripheral and autonomic neuropathy and renal and gastroenterological disorders.

Treatment for Complications of Amyloid Heart Disease

The Brigham and Women’s team works to ease any complications associated with cardiac amyloidosis. A few areas that are closely monitored include:

• Sodium Intake. Patients with cardiac amyloidosis tend to retain a lot of fluid and are sensitive to sodium intake. Diuretics (medications that remove excess sodium and fluid from the body) are the main drugs of therapy for symptoms of excess sodium.
• Unstable blood pressure. This can be improved by simple measures like compression stockings or medications, such as midodrine.
• Side effects from common cardiac drugs. Some drugs can cause problems in those with cardiac amyloidosis and must be administered with caution.

Lifestyle Changes

Lifestyle changes can also help limit risk factors, including:

• Weight loss
• Fat and salt reduction in diet
• Blood pressure control

Due to innovation in treatment, the prognosis for cardiac amyloidosis has improved and patients often live for multiple years following a diagnosis. Without treatment, cardiac amyloidosis commonly results in death within a year.