Treatment of viral myocarditis caused by coxsackievirus B.

PURPOSE: The treatment options for viral myocarditis caused by coxsackievirus B are summarized.

SUMMARY: Myocarditis is a common cause of dilated cardiomyopathy. The most common causes of infectious myocarditis are viruses. The exact mechanism of coxsackievirus B-induced damage to myocytes is unknown. The likely mechanisms involve immune-mediated and direct viral cytotoxicity. There are several proposed treatment strategies that target specific points in the pathway from myocarditis to cardiomyopathy. Immunosuppressive agents (azathioprine, prednisone, and cyclosporine) for the treatment of myocarditis seem logical, since one of the mechanisms thought to contribute to myocarditis is autoimmune destruction. Another treatment option of viral myocarditis is intravenous immunoglobulin (IVIG). As with conventional immunosuppressive strategies, IVIG suppresses the immune response. In addition, IVIG may replace antibodies, enhance viral clearance, neutralize pathogens, and enhance clearance of inflammatory cytokines that contribute to myocytes destruction. Antiviral agents, such as interferons, pleconaril, and acyclovir, target the causative organism, possibly halting the cascade of myocyte destruction. Natural products of particular interest in the treatment of viral myocarditis are Astragalus membranaceus and Ardisia chinensis. There is no specific therapy for patients with viral myocarditis or dilated cardiomyopathy. In general, patients with dilated cardiomyopathy will benefit from agents commonly used in heart failure, since their symptoms and presentation are similar.

CONCLUSION: Immunosuppressive agents, IVIG, antiviral agents, and natural medicines have been used in the treatment of patients with myocarditis. However, the efficacy of these agents has not been well established, partly because research has not differentiated between infectious and noninfectious myocarditis. This makes it difficult to extrapolate study results to viral myocarditis.