Giant Left Atrial Pleomorphic Sarcoma With Echocardiographic Characteristics Mimicking a Myxoma

Primary cardiac tumors are rare. Cardiac tumors of substantial size may present in the perioperative setting urgently, bypassing conventional imaging, thus relying on echocardiography for characterization and operative guidance. We report a unique case of a 66-year-old female with a large left atrium mass, who presented with worsening dyspnea and fatigue, with biopsy suggesting a primary cardiac sarcoma. This case is unique, as approximately 70% of left atrial masses reported in the literature are cardiac myxomas, whereas the most common site in which cardiac sarcomas develop is the right atrium. In this particular case, the location of the left-sided sarcoma resulted in mitral valve and left ventricular outflow obstruction, as well as severe pulmonary hypertension, leading to complicated anesthetic induction during surgery. This rare case of a primary cardiac tumor highlights the sequelae of obstructive atrial masses, which potentially resulted in cardiovascular collapse with induction of anesthesia. It is especially unique for pathologic findings suggesting a cardiac sarcoma. This case provides an opportunity to discuss diagnostic challenges for patients with complex pathophysiology and contributes to the limited collection of literature on cardiac sarcomas located in the left atrium.