Cardiac amyloidosis masquerades as other conditions; 1 type affects more black AmericansMayo Clinic
Human bodies constantly produce thousands of perfectly folded proteins, but some proteins get misfolded. An excess of these misfolded proteins can overwhelm the body's ability to remove them. When that happens, the rogue proteins bind together and form a substance called amyloid. Webs of amyloid can deposit in any tissue or organ, but some types affect the heart.