Role of inflammation in the progression of heart failure.

Chronic heart failure (HF) is a disorder characterized in part by immune activation and inflammation. Thus, patients with HF have elevated levels of a number of inflammatory cytokines, both in the circulation and in the failing heart itself. Several mechanisms for this immune activation, which are not mutually exclusive, have been suggested, including neurohormonal activation, hemodynamic overload, and activation of the innate immune system secondary to cardiac stress. Importantly, experimental studies have shown that inflammatory cytokines such as tumor necrosis factor-alpha, interleukin-1b, and monocyte chemoattractant peptide-1 may contribute to the development and progression of HF by promoting myocardial hypertrophy, activating matrix metalloproteinases, provoking contractile dysfunction, and inducing apoptosis. However, inflammatory cytokines may also have adaptive and cardioprotective effects. This important aspect of cytokine biology must be kept in mind when designing new immunomodulatory treatment modalities in HF.