Cardiac myxomas are the second most common primary heart tumours, after papillary fibroelastomas. They mostly arise in the left atrium from the fossa ovalis region. The etiology is still not precisely determined, but the myxoma cells harbour similar protein expression described in endocardial-mesenchymal transformation of the endocardial cushion [1,2]. Most of them are sporadic, but about 10 % are associated with the Carney complex, an autosomal dominant disorder caused by mutations in protein kinase A regulatory subunit 1 alpha (PRKAR1A). It is characterized by myxomas in the heart (in atypical locations), skin and breast; they tend to be multiple and recur. Moreover, patients might develop endocrinopathies and mucocutaneous pigmentations. Sporadic cases are more common in women and familial ones in men. Most myxomas are found in the 3rd through 6th decades of life [3].

Myxomas can cause cardiac symptoms due to mass effect and break off with consequent embolism. Systemic symptoms such as fever, malaise, weight loss, arthralgia and others are explained by myxoma cells' secretion of inflammatory cytokines (IL-4, IL-6, IL-12, interferon-γ, and TNF)  and other substances [4].

Grossly, they can be rounded (solid) or papillary (filiform), sessile or pedunculated (with a stalk). The diagnosis is based on histological examination, finding characteristic myxoma cells, also known as lepidic cells, embedded in a myxoid matrix. The myxoma cells are cytologically bland, with ovoid or round nuclei and eosinophilic cytoplasm. They are singly dispersed through the matrix or form clusters; these clusters can be around vessels, creating rings around them. Inflammatory and posthemorrhagic changes are frequently encountered as a result of repeated damage during the cardiac cycle. Immunohistochemical analysis might help diagnose a myxoma. Usually, positive markers comprise calretinin, S100, CD31 and CD34. PRKAR1 expression might help exclude the Carney complex because its loss raises the possibility of the syndrome [1,3].

Myxomas are treated by surgical resection, harbouring an overall good prognosis. The recurrence rate of sporadic cases is about 5%; for familial cases, it reaches up to 10-20 % [5], [6], [7].