Combined Mechanism of Refractory Shock in Primary Cardiac Lymphoma: A Rare Dilemma

Primary cardiac lymphoma is very rare, and usually manifests after the fifth decade of life. The lack of typical manifestations makes it difficult to diagnose at an early stage that can be discovered only by echocardiography. The location of the tumour often results in cardiac compromise, which prevents the delivery of potentially curative therapies. Clinical presentations may depend on flow obstruction, infiltration of adjacent tissues, tumour embolisation, and atrioventricular (AV) disturbances. We report a rare case of primary cardiac lymphoma that presented with clinical signs of shock from two distinct mechanisms. The first mechanism was intermittent complete AV block that was caused by disruption of the electrical conduction system from tumour infiltration in addition to direct mechanical compression of the atrioventricular node by the tumour. The second mechanism, subtotal RV inflow obstruction from the bulky mass contributed to compromising venous return, which played a major role of refractory shock in this case.