Possible Precipitation of Acute Coronary Syndrome with Immune Checkpoint Blockade: A Case Report

Immune checkpoint inhibitors (ICI) have led to improved survival in patients with a number of different tumor types. The ICI agent nivolumab induces anti-tumor immune responses by inhibiting the programmed cell death 1 protein, but side effects include cardiac immune-related adverse events (irAE) such as myocarditis.¹ The association of nivolumab with atherosclerotic disease has been rarely reported.A 62-year-old man with metastatic melanoma and recent myocardial infarction (MI) presented with recurrent MI after having undergone several cycles of nivolumab therapy. Repeat cardiac catheterization revealed rapidly progressive in-stent restenosis and diffuse coronary artery disease (CAD) requiring bypass surgery and warranting cessation of nivolumab therapy.Nivolumab has been linked with dysregulation of immune responses including enhanced T cell activity, which is implicated in CAD. The timing of nivolumab therapy and presentation with non ST elevation myocardial infarction in this patient suggests a serious T cell-driven medication adverse effect. Therefore, close monitoring for atherosclerotic disease progression is warranted in patients on immunotherapy.