Real-world cardiovascular toxicity of immune checkpoint inhibitors

In clinical trials, immune checkpoint inhibitors (ICIs) have been associated with the development of cardiovascular (CV) adverse events (AE). However, as patients with cardiac comorbidities were largely excluded from these clinical studies, the incidence of CV AEs is probably underestimated. To address this issue, Danielle Delombaerde, pharmacist at the Integrated Cancer Center in the General Hospital AZ Maria Middelares in Ghent and colleagues set up a study to describe the incidence of CV events in a real-world cohort of Belgian cancer patients who were treated with an ICI. 

This analysis included a total of 1,571 patients who received at least 1 ICI cycle between March 2017 and August 2022 in 3 Belgian hospitals. The main conclusion of the study is that the frequency of CV events is indeed higher in real life than what was observed in clinical trials. The 12.5% incidence reported in this cohort was similar to what was described in other real-world studies. Interestingly, the study also revealed that these CV events can have a very late onset. For example, the median time of onset for an acute myocardial infarction, or pericarditis was reported at 210 and 243 days, respectively. Takotsubo cardiomyopathy can develop even later, with a median time of onset in this analysis of 529 days. 

In conclusion, clinicians should know that CV AEs occur frequently in cancer patients treated with an ICI and that these events can develop at any time during or after treatment.