P55 A CHALLENGING RIGHT ATRIAL MASS

Abstract

Abstract A 64–year–old woman presented at the Emergency Department with worsening dyspnoea and fever. Blood tests revealed normal white blood count, elevated C–reactive protein (244 mg/L) and D–dimer (2618 ng/mL). At arterial blood gases test hypoxaemia and hypocapnia was found (pH 7.48, pO2 83 mmHg, pCO2 30 mmHg, base excess –1.2 mmol/L, lactates 1.0 mmol/L). She underwent thoracic computed tomography (CT), which showed right inferior pulmonary embolism with infarction. A transthoracic echocardiography (TTE) revealed the presence of a mobile heterogeneous iso–hyperechoic neoformation completely occupying the right atrial cavity and moving partially across the tricuspid valve (Figure 1). A right atrial thrombotic formation was hypothesized and, due to its dimension, despite a valid hemodynamic, the patient underwent thrombolysis with rtPA 100 mg iv infusion over 2 hours. However, the next day at CT and TTE the mass was still there and unmodified. The screening for thrombophilia and for cancer markers were negative. Cardiac magnetic resonance imaging was waived because the clinical conditions were rapidly deteriorating. Indeed, the patient was transferred for urgent cardiac surgery. The excised mass was 5 cm x 3.5 cm large and adherent to the right atrial roof, 1 cm close to the atrioventricular node. It was completely removed by the cardiac surgeon (Figure 2). The subsequent journey was regular, without complications. The histologic exam revealed that the mass was a giant myxoma (Figure 3). At follow–up the patient persisted asymptomatic. Figure 1. Transthoracic echocardiography. Figure 2. The excised right atrial mass. Figure 3. Histologic examination of the right atrial mass.