(A) Pulmonary valve (autopsy specimen, viewed from above). Diffuse carcinoid plaques have caused thickening and retraction of all three cusps and appreciable constriction of the annulus (valve ring). The result is a small fixed triangular orifice that was both stenotic and regurgitant clinically. (B) Normal pulmonary valve, for comparison with (A) (autopsy specimen, viewed from above). All three cusps are thin and coapt (come together) centrally, and the annulus (valve ring) is neither constricted or dilated.
Courtesy of Dr. William D. Edwards, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota.
