Doxorubicin is a chemotherapy drug used in ovarian, bladder, lung, thyroid and stomach cancers, but it carries a harmful side effect. The drug causes a dose-dependent heart toxicity that can lead to congestive heart failure. Researchers have found an important contributor to that heart pathology — disruption of the metabolism that controls immune responses in the spleen and heart. This dysregulated immunometabolism impairs resolution of inflammation, and chronic, non-resolving inflammation leads to advanced heart failure.