Large right atrial myxoma containing gastric heterotopia presenting with dyspnea and bilateral leg edema due to pulmonary emboli and cardiovascular obstruction: the first known report of gastric heterotopia in the cardiovascular system.

A 52-year-old male presented with progressive dyspnea, bilateral leg edema, and elevated central venous pressure due to a large right atrial myxoma that caused vascular obstruction and pulmonary emboli. The myxoma contained gastric heterotopia. Other unusual features of this atrial myxoma included its large size, right atrial location, and attachment to the right atrial wall. Although gastric heterotopia has been reported throughout the gastrointestinal tract, and occasionally in other organs, this is the first report of gastric heterotopia in the cardiovascular system. This report confirms and extends previous reports of glandular elements or enteric glands within atrial, or cardiac, myxomas. The clinical presentation of the currently reported patient is explained as follows: the elevated central venous pressure resulted from cardiovascular obstruction and the dyspnea from multiple pulmonary emboli due to the large atrial myxoma. In this case, the clinical presentation was not attributable to the gastric heterotopia. The association of gastric heterotopia with atrial myxoma may, however, be clinically important because of the propensity of gastric heterotopia in the gastrointestinal tract to produce complications. The reported association may provide clues to the histogenesis of these two entities.