Cisto de sangue

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6726829/#!po=43.7500

Presentation of cardiac blood cysts in adulthood is rare. Moreover, a few of these cases occasionally develop complications, such as valvular dysfunction, embolic stroke, and ventricular outflow system obstruction.^1,2 We report a case of an adult male patient who developed frequent syncope due to mitral valve blood cysts occluding the aortic orifice. This condition was detected by transthoracic and contrast echocardiography.

https://www.cureus.com/articles/23662-evaluation-of-mitral-apparatus-blood-cyst-a-case-report-and-review-of-literature