A case of irreversible bradycardia after rituximab therapy for diffuse large B-cell lymphoma

Abstract

This is a case of a middle-aged woman with underlying cardiac conduction system with episodes of AV Wenckebach, who subsequently developed significant AV conduction system abnormalities after receiving one standard dose of Rituximab infusion for diffuse large B-cell lymphoma. Rituximab, being a monoclonal antibody against CD-20 antigen, is effective in treatment of B-cell lymphoma but may also cause bradyarrythmias likely due to the calcium ion channel property of CD-20 antigen.

Bradyarrhythmias in Cardio-Oncology

“… 20 Two case reports of CHB have been published, but one of the patients had previous conduction disease, and the other was an aged patient; hence the causality is difficult to ascertain. 21 22 It was postulated that rituximab might affect the cardiac conduction system by inhibiting Ca 2+ channel properties of the CD20 antigen on cardiac myocytes. 22 …”

An Unusual Case of Delayed-Onset Rituximab-Induced Ventricular Tachycardia: A Case Report

“…One review has presented evidence that the incidence of supraventricular tachycardia was higher in the group received rituximab in addition to standard cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) therapy vs CHOP therapy alone. 5 There are cases of other non–ventricular tachycardia (VT)-related events which appear to affect all parts of the heart (conduction, structural, coronary circulation) including irreversible bradycardia, 6 non-ischemic cardiomyopathy, 7 coronary vasospasm, 8 and coronary artery occlusion and associated ST-elevation myocardial infarction. 9 …”

Symptomatic Bradycardia Post Rituximab Infusion

“…Bradycardia has rarely been reported with rituximab, both in patients with normal and abnormal conduction systems. 1 It is presumed to occur due to impairment of CD20 antigen, which functions as a calcium ion channel. 2 Although our patient had multiple risk factors for bradycardia such as the use of diltiazem, metoprolol, moxonidine, and subclinical hypothyroidism, yet he had a consistently normal HR, and symptomatic bradycardia only occurred after rituximab infusion.…”