Immune checkpoint inhibition and heart injury: molecular mechanisms and clinical challenges

Immune checkpoint inhibitors (ICIs), such as PD-1, PD-L1, and CTLA-4 inhibitors, enhance immune function by targeting T-cell surface receptors, overcoming natural immune inhibition. These drugs activate the immune system to detect and target cancer cells, providing an alternative therapeutic approach, particularly in cases where conventional treatments fail. However, the growing use of ICIs has highlighted several defence-related adverse events, particularly cardiac toxicity, including acute myocarditis, atherosclerosis, and heart failure unrelated to myocarditis. These complications present significant challenges, limiting the broader use of ICIs. Research into the cardiac toxicity of ICIs is still in its early stages, and the underlying mechanisms remain unclear. This review consolidates current findings on ICI-associated heart damage, explores potential factors contributing to ICI-induced cardiac injury, and evaluates preventive and therapeutic strategies. This work aims to provide a theoretical foundation for medical intervention and prevention of ICI-related cardiac damage.