TY - JOUR T1 - Primary Cardiac Angiosarcoma Leading to Tamponade and Fatal Right Atrial Rupture. AU - Makaroff,Katherine E, AU - Hampilos,Katherine, AU - Sayed,Sammy, AU - Emert,Benjamin, AU - Hu,Xuchen, AU - Nsair,Ali, AU - Kwon,Murray, AU - Middlekauff,Holly, Y1 - 2026/05/28/ PY - 2026/03/16/received PY - 2026/03/29/revised PY - 2026/04/06/accepted PY - 2026/5/28/medline PY - 2026/5/28/pubmed PY - 2026/5/28/entrez KW - cardiac neoplasm KW - cardiac tamponade KW - cardiac tumor KW - pericardial effusion KW - pericarditis KW - primary cardiac angiosarcoma SP - 108385 EP - 108385 JF - JACC. Case reports JO - JACC Case Rep N2 - BACKGROUND: While rare, primary cardiac tumors, especially angiosarcomas, have a high mortality rate and are difficult to diagnose due to vague symptoms and limited visibility on transthoracic echocardiogram. CASE SUMMARY: A 47-year-old patient was treated for acute pericarditis with transient resolution of a pericardial effusion but persistent dyspnea, chest pain, fatigue, and elevated inflammatory markers. Six months after the initial presentation, they developed tamponade, had hemorrhagic shock, and passed away due to right atrial rupture from an infiltrative tumor. Pathology demonstrated primary cardiac angiosarcoma. DISCUSSION: This case illustrates the diagnostic challenges and consequences of a cardiac tumor which was not apparent on serial echocardiograms. TAKE-HOME MESSAGES: Primary cardiac malignancy should be considered in the setting of recurrent pericardial effusion with systemic symptoms and persistently elevated inflammatory markers. Echocardiogram has shown low sensitivity for cardiac tumors in the setting of effusion; advanced imaging modalities can facilitate early detection and intervention. SN - 2666-0849 UR - https://www.unboundmedicine.com/prime/citation/42207063/Primary_Cardiac_Angiosarcoma_Leading_to_Tamponade_and_Fatal_Right_Atrial_Rupture. DB - PRIME DP - Unbound Medicine ER -