Primary cardiac lymphoma presenting with wide QRS tachycardia: a case report.

Background: Lymphomas, which originate from the haematopoietic system, are seldom found in the heart due to the absence of a lymphoid system. Primary cardiac lymphoma is quite rare. Cardiac lymphomas can present with dyspnoea, heart failure, pericardial effusion, and arrhythmia. Given the high mortality rates associated with cardiac masses, swift diagnosis is crucial. Case summary: A 46-year-old male patient presented to the emergency department of our hospital with complaints of dyspnoea and palpitations. The patient's electrocardiogram revealed a tachycardia characterized by a wide QRS complex and a heart rate of 234 beats per minute, and an intravenous infusion of amiodarone was immediately started. In the cardiac MRI performed, a mass lesion was observed, which was ∼63 ∗ 30 ∗ 79 mm in size, extending from the right atrium to the superior vena cava and right atrial appendage, infiltrating the free wall of the right ventricle, pericardium, and right atrial wall, and showing distinct diffusion restriction in places. The patient's cardiac MRI was documented with a suspicion for cardiac lymphoma. The patient was referred to haematology clinic and started on rituximab-cyclophosphamide, doxorubicin, vincristine, and prednisone chemotherapy. Discussion: The diagnosis of primary cardiac lymphoma is uncommon. Even a mass exceeding 7 cm in size may not be visible on transthoracic echocardiography. The use of cardiac MRI to identify intracardiac masses should be incorporated into the diagnostic process to expedite diagnosis and the initiation of life-saving treatment.