Atrial fibrillation with aberrant ventricular conduction after receiving Bamlanivimab/Etesevimab: a case report.

Coronavirus Disease 2019 (COVID-19) is affecting millions of people globally. Several neutralizing monoclonal antibodies have been developed to limit the progression and complications of the disease. These treatments provide immediate and passive immunity. The combination therapy with Bamlanivimab plus Etesevimab led to a lower incidence of COVID-19-related hospitalization and death and a faster reduction in the SARS-CoV-2 viral load. No or rare cases of cardiovascular side effects are reported. We present the case of a high-risk 79-years-old woman who developed atrial fibrillation with aberrant ventricular conduction after administration of neutralizing monoclonal-antibodies Bamlanivimab plus Etesevimab. The woman with a history of insulin-dependent diabetes and Grade II follicular Non-Hodgkin Lymphoma previously vaccinated with two doses of Pfizer COVID-19 vaccine, presented with malaise, headache, and SARS-CoV-2 nasal swab reverse transcription-polymerase chain reaction tested positive for the infection. She received a single dose of Bamlanivimab (70 mg) + Etesevimab (1400 mg). After about a week, she developed atrial fibrillation with uncontrolled response to frequent premature ventricular complexes and aberrant ventricular conduction. This case presents a high-risk woman with SARS-CoV-2 infection who developed a serious adverse cardiovascular event some days after receiving neutralizing monoclonal antibodies. Risk factors including sex, age, anxiety related to isolation and infection, and COVID-19 itself may have all contributed to atrial fibrillation. Arrhythmia may rarely occur after monoclonal-antibodies treatment, although recommended timing to monitor patients is from 1 to 24 h after the administration of these antibodies. Appreciation of this potential association is important for evaluating monoclonal-antibody treatments' safety and optimizing patient monitoring and follow-up.