Introduction:
Pembrolizumab is a humanized IgG4 antibody that disrupts the interaction
between programmed cell death protein 1 (PD1) and programmed
death-ligand 1 (PDL1)1. It belongs to the
immune-checkpoint inhibitors (ICI) class, which has been shown to
enhance clinical outcomes in a variety of solid organ
cancers2. Despite positive therapeutic outcomes, this
new medicine is associated with a slew of negative side effects.
Pembrolizumab-related immune-related side effects include myocarditis
and neuromuscular side effects are uncommon. However, there is growing
evidence of an increased risk of ICI-related myocarditis. There is no
clarity on diagnosis or therapeutic management that we are aware of.
Myocarditis, cardiomyopathy, heart failure, and arrhythmias are all
associated cardiotoxicities. The offending agent is usually stopped in
the majority of cases of immune checkpoint inhibitor
cardiotoxicity3. We discuss a case of a patient who
developed cardiomyopathy as a result of pembrolizumab treatment and was
successfully managed.