Tc-99m HDP uptake in cardiac amyloidosis.

Amyloidosis is characterized by the soft-tissue deposition of amyloid protein. It may occur as a primary disorder but more often is seen as a manifestation of chronic illness. Scattered reports of the affinity of amyloid for bone scanning agents have appeared over many years. Isolated cardiac uptake of Tc-99m HDP is described in a patient with biopsy-proved cardiac amyloidosis on a background of tuberculosis, prostate cancer, and coronary artery disease.