• Metka Šimundić
  • Aleksandra Domanjko Petrič
  • Darja Pavlin
  • Tadej Zemljič
  • Igor Firm
  • Mitja Gombač
  • Špela Srečnik
  • Mateja Stojov
  • Laura Šimenc
  • Tanja Švara Veterinary Faculty University of Ljubljana



Cardiac tumours occur very rarely in domesticated animals and humans. The most common cardiac tumours in dogs are hemangiosarcoma and chemodectoma. Myxoma, on the other hand, occurs extremely rarely. In this report, we present a case of an 11-year-old, spayed, mixed-breed dog with a myxoma arising from the tricuspid valve. The dog presented with syncope, tachypnea, tachycardia, exercise intolerance and progressive ascites. Two-dimensional echocardiography showed a polypoid intracavitary mass in the right heart. At necropsy, a polypoid, red mass was observed arising from the tricuspid valve. Histologically, the mass was composed of spindle-shaped and stellate cells with small hyperchromatic nuclei surrounded with myxoid matrix. After performing immunohistochemistry, the neoplastic cells were found to be strongly positive for vimentin. Based on gross, microscopic, and immunohistochemical staining features, the neoplasm was diagnosed as a cardiac myxoma. 

Key words: myxoma; heart; dog; two-dimensional echocardiography; histopathology; immunohistochemistry



Povzetek: Tumorji srca so pri živalih in ljudeh redki. Pri psih se v srcu najbolj pogosto pojavljata hemangiosarkom in kemodektom, pojavnost miksomov pa je izjemno nizka. V prispevku predstavljamo primer miksoma triksupidalne zaklopke pri psički mešanki, stari 11 let. Psička je prišla na pregled zaradi enkratne sinkope in ker je bila bolj mirna in utrujena. Ugotovili smo tahikardijo, tahipnejo in progresivni ascites. Z dvodimenzionalno ultrazvočno preiskavo smo v desnem delu srca ugotovili polipoidno intrakavitarno maso. Pri raztelesbi smo ugotovili, da je polipoidna, temno rdeča novotvorba izraščala iz parietalnega lista triksupidalne zaklopke. Mikroskopsko je bila novotvorba zgrajena iz vretenastih in zvezdastih celic, z majhnimi, hiperkromatičnimi jedri, ki jih je obdajal miksoidni matriks. Z imunohistokemičnim barvanjem smo potrdili, da so novotvorbne celice izražale vimentin. Novotvorbo smo na osnovi makroskopskih in mikroskopskih značilnosti diagnosticirali kot miksom srca.

Ključne besede: miksom; srce; pes; dvodimenzionalna ultrazvočna preiskava; histopatologija; imunohistokemija

Author Biography

Tanja Švara, Veterinary Faculty University of Ljubljana

Institute of Pathology, Wild Animals, Fish and Bees


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How to Cite

Šimundić, M., Domanjko Petrič, A., Pavlin, D., Zemljič, T., Firm, I., Gombač, M., Srečnik, Špela, Stojov, M., Šimenc, L., & Švara, T. (2019). CARDIAC MYXOMA IN A DOG. SLOVENIAN VETERINARY RESEARCH, 56(3).



Case Report