Sudden death due to lymphomatous infiltration of the cardiac conduction system.

We present the case of a 62-year-old white female with a history of previously treated angioimmunoblastic T-cell lymphoma, who died suddenly 1 day after presentation for presumed tumor recurrence. Postmortem gross examination revealed a 4-cm cardiac mass that was adherent to the free wall of the right atrium. Histologic examination showed extensive infiltration of the cardiac conduction system by lymphoma, which likely lead to fatal arrhythmia. Histological examination revealed systemic dissemination by an Epstein-Barr virus (EBV)-positive large B-cell lymphoma. Careful examination of the cardiac conduction system on serial sections was crucial in documenting the cause of death due to lymphomatous infiltration. As in this patient, lymphomatous infiltration of the heart may produce sudden cardiac death without obvious premortem signs of cardiac compromise. This case illustrates the utility of examination of the cardiac conduction system in necroscopy studies of sudden death.