• myocarditis;
  • CD4+ T cells;
  • Th17 cells;
  • autoimmune disease;
  • cytokines

This review focuses on autoimmune myocarditis and its sequela, inflammatory dilated cardiomyopathy (DCMI), and the inflammatory and immune mechanisms underlying the pathogenesis of these diseases. Several mouse models of myocarditis and DCMI have improved our knowledge of the pathogenesis of these diseases, informing more general problems of cardiac remodeling and heart failure. CD4+ T cells are critical in driving the pathogenesis of myocarditis. We discuss in detail the role of T helper cell subtypes in the pathogenesis of myocarditis, the biology of T cell–derived effector cytokines, and the participation of other leukocytic effectors in mediating disease pathophysiology. We discuss interactions between these subsets in both suppressive and collaborative fashions. These findings indicate that cardiac inflammatory disease, and autoimmunity in general, may be more diverse in divergent effector mechanisms than has previously been appreciated.