Hamartoma of the mitral valve with blood cysts: a rare tumor detected by echocardiography.

A 16-year-old boy was submitted to a cardiac examination after an episode of faintness. A transthoracic echocardiogram was performed, which revealed a very mobile multicystic tumor attached to the mitral valve. A small solid mass adherent to the cysts was better defined by transesophageal echocardiography. The patient was submitted to cardiac surgery consisting of tumor resection and a mitral prosthesis implant. The surgery was successful. The tumor consisted of three bright red tense cysts with hematic content, each 1 to 2 cm in diameter. The cysts were coalescent and adherent to a solid mass attached to the posterior papillary muscle head. Histopathologic examination revealed a hamartoma with a cystic part composed of the proliferation of myofibroblast cells in a stroma with vessels, collagen, and elastin fibers. Valvular hamartoma with blood cysts is a very rare cardiac tumor both for its histopathology and its localization.