Signs and Symptoms

Because many signs and symptoms may be related to many other conditions, cardiac amyloidosis can be difficult to diagnose. For example, because cardiac amyloidosis can cause shortness of breath and swelling, it may be misdiagnosed at first as just heart failure.

Some people may not have any symptoms until the misfolded protein builds up, crowding out and replacing normal heart tissue.

Over time, amyloidosis can change the structure and function of your heart because the walls of the heart become thicker and stiffer, which makes it hard for the muscle to relax and contract and pump blood. It can also lead to heart failure and disrupt heart rhythms resulting in abnormal rhythms that can be too fast or too slow.

If you have cardiac amyloidosis, you may have:

• Shortness of breath with activity or when lying down
• Weakness
• Extreme tiredness
• Heart palpitations, feel your heart racing or skipping beats (arrhythmias)
• Swelling in your belly, legs, ankles, or feet
• Low blood pressure or dizziness when standing up or changing positions
• Fainting or lightheadedness
• Numbness or tingling in the hands or feet

Learn more: Different types of amyloidosis

Interestingly, many people with cardiac amyloidosis have a history of musculoskeletal problems too. ATTR amyloidosis, in particular, can also involve ligaments and tendons. Carpal tunnel syndrome (pressure on a nerve that passes through the carpal tunnel), lumbar spinal stenosis (a narrowing in the spine that compresses or puts pressure on the nerves) and joint replacements are common in people with ATTR. All of these are red flags that should raise the suspicion for cardiac amyloidosis. Neurologic symptoms such as numbness and tingling in the hands and feet may also occur.

About 15% of people with heart failure in which the pumping ability of the heart is still normal (called heart failure with preserved ejection fraction, or HFpEF) and 15% of people who undergo a procedure to get a new aortic valve actually have cardiac amyloidosis.