In myocarditis, T lymphocytes (T cells), have been reported to home the myocardium and to acutely reduce left ventricular (LV) function and this has been associated with increased levels of circulating cytokines, such as TNF-α which led to the prioritization of proinflammatory cytokines as markers of myocarditis and heart failure. The gene discussed is TNF; the disease is myocarditis.