Sudden unexpected death from subvalvular hemorrhagic cyst complicated with coronary heart disease in an adult.

Cardiac blood cysts are rare benign tumors. It is commonly found in the heart valve and left ventricle of newborns by autopsy and is rarely seen in adults [1, 2]. The typical histopathology of cardiac blood cysts is a closed, round, blood-containing cystic mass attached to the heart valve or endocardium. This article reports a rare case of sudden death due to a giant subaortic cardiac blood cyst with coronary heart disease in an adult patient and summarizes the pathological features, aiming to provide a reference for the forensic pathological identification of cardiac blood cysts.