A, Endomyocardial biopsy specimen, stained with hematoxylin and eosin, from a patient with cardiac amyloidosis. The amyloid stains light pinkish red and is seen as an amorphous material that separates the darker staining myocytes. B, Staining of the tissue from the same patient using sulfated Alcian blue. The amyloid stains turquoise green and the myocytes stain yellow, characteristic of amyloid. Courtesy of Dr Gayle Winters, Brigham and Women’s Hospital. Boston, Mass.