1636 Endomyocardial biopsy of right atrial mass with unfortunate consequence of right-to-left shunt

Abstract

Abstract Funding Acknowledgements Nil A 43-year old lady complained of dyspnoea with elevated jugular venous pressure. Transthoracic echocardiography (TTE) showed massive pericardial effusion [Figure 1A] with a huge heterogeneous mass (5x9cm) attached to right atrial free wall [Figure 1B]. Therapeutic pericardiocentesis yielded blood-stained pericardial fluid with negative for tumour cells. Endomyocardial biopsy (EMB) was performed under transthoracic echocardiography (TTE) and fluoroscopy guidance. Right after procedure, there was a significant desaturation which could not be reversed by high flow oxygen supplement. The acute hypoxaemia was secondary to right-to-left shunt through a wide-open patent foramen ovale (PFO) as shown by transoesophageal echocardiography (TOE) [Figure 2A-D]. Transcatheter PFO closure was performed under TOE guidance with immediate correction of hypoxemia. [Figure 3]. Subsequent Computer Tomography demonstrated a large vascular mass at right atrium abutted onto the basal right ventricle and tricuspid valve [Figure 4] without evidence of tumor embolism. The histological diagnosis confirmed it was a cardiac sarcoma. Given the infiltrative nature of cardiac sarcoma with significant right ventricular (RV) inflow obstruction, a debulking surgery was done rather than a complete curative resection. She was referred to oncologist for adjuvant chemotherapy. We postulated that there is a shift in tumour location, i.e. more towards the tricuspid valve orifice which results in elevated right ventricular inflow obstruction which triggers the acute right-to-left shunting through PFO. Abstract 1636 Figure. EMB