Emergency Surgery for Left Atrial Angiosarcoma Presenting with Acute Respiratory Failure: A Fatal Case Report

INTRODUCTION: Primary cardiac angiosarcoma is an extremely rare and aggressive malignancy with a poor prognosis. Herein, we describe a case of left atrial angiosarcoma presenting with acute respiratory failure that required emergency surgical intervention, highlighting the condition’s diagnostic and therapeutic challenges. CASE PRESENTATION: On routine chest radiography, a mass shadow in the right lower lung field was detected in a 75-year-old male, initially suspected to be lung cancer or a pulmonary abscess. During hospitalization for diagnostic workup, the patient’s respiratory function suddenly deteriorated upon mobilization. In addition, contrast-enhanced CT revealed a large intracardiac mass occupying the left atrium. Following emergent intubation for severe hypoxemia, he was transferred to our institution for surgical intervention. Laboratory findings showed elevated inflammatory markers (white blood cells, 22850/μL; C-reactive protein, 15.9 mg/dL), coagulopathy (D-dimer, 18.67 μg/mL), and severe metabolic acidosis (pH 7.15; lactate, 31 mmol/L). Transesophageal echocardiography confirmed a large mass filling the left atrium, nearly incarcerated in the mitral valve orifice. Subsequently, emergency surgery was performed under cardiopulmonary bypass. Through a right atrial and transseptal approach, the friable tumor filling the left atrium was removed. However, the right lower pulmonary vein inlet showed extensive tumor involvement with residual attachment. Despite extensive resection and thorough cavity irrigation, complete resection could not be definitively confirmed. Initially, the patient regained consciousness without neurological deficits and was successfully weaned from mechanical ventilation on POD 6. However, severe tachypnea and copious bloody sputum production developed on POD 7, necessitating reintubation and tracheostomy. Despite hemodynamic stability, he experienced progressive type II respiratory failure, which caused his death on POD 14. Histopathological analysis revealed positivity for vascular endothelial markers (CD31, ERG, factor VIII) and absence of MDM2 expression, confirming the diagnosis of angiosarcoma. Pulmonary hemorrhagic necrosis from tumor infiltration or pulmonary tumor thrombotic microangiopathy might have caused his rapid respiratory deterioration. CONCLUSIONS: Left atrial angiosarcoma can present with acute life-threatening complications requiring emergency surgery. Despite successful tumor debulking, the prognosis remains poor because of aggressive tumor biology and potential pulmonary metastases. This case emphasizes that management of primary cardiac angiosarcoma remains challenging despite prompt surgical intervention.