Transient Asymptomatic Sinus Bradycardia and Sinus Pauses with Bevacizumab: Case Report and Literature Review

Systemic side effects of anti-cancer therapy remain a major limiting factor for patients, even with targeted therapy. Bevacizumab is an example of targeted cancer therapy which targets the vascular endothelial growth factor receptor (VEGFR) that has been approved for the treatment of various cancers and has been evaluated in metastatic urothelial carcinoma (MUC). We report a case of MUC on bevacizumab containing regimen who developed temporary asymptomatic sinus bradycardia with sinus pauses. That adverse event was thought to be related to the bevacizumab in her cancer regimen. Her Holter monitoring recording for a total duration of 28 days and 14 h after discharge did not show recurrence of sinus pauses. This case indicates the necessity for observation for the cardiac conduction defects as side effects in patients receiving bevacizumab, especially since they might be asymptomatic and transient.