Coronary sinus obstruction by primary cardiac lymphoma as a cause of dyspnea due to significant diastolic dysfunction and elevated filling pressures.

A 52-year-old woman presented with severe dyspnea of 2 weeks' duration. Echocardiography showed an enlarged left atrium but normal global left ventricular systolic function. However, a huge, irregularly shaped mass at the dilated coronary sinus that extended into the right atrium was noted. Mitral inflow showed restrictive physiology and the E/E' ratio was significantly elevated, suggesting elevated left ventricular filling pressures. Echocardiography-guided biopsy was performed, and a diagnosis of primary cardiac lymphoma (diffuse large B-cell type) was made. After the first cycle of chemotherapy, the patient's symptom was markedly improved. A follow-up echocardiogram showed complete removal of the mass and a change in left ventricular filling pattern from restrictive to relaxation abnormality with decreased E/E'. The present case demonstrates a rare cause of diastolic dysfunction due to coronary sinus obstruction by tumor infiltration. Diastolic dysfunction caused by coronary sinus obstruction was improved after the tumor was resolved by chemotherapy. Copyright 2010 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.