HHV-6 infection has been reported to cause cardiac complications in both the immunocompromised and the immunocompetent, including myocarditis (Ashrafpoor 2013Leveque 2011, Mahrholdt 2006), dilated cardiomyopathy (Tatrai 2011), sinus tachycardia (Nishimoto 2012), and “idiopathic” left ventricle dysfunction (Kühl 2005). Furthermore, in 2013 a child with drug-resistant HHV-6B myocarditis was successfully treated with Artesunate, an antimalarial medication known to have efficacy against HHV-6 (Hakacova 2013). Despite increasing reports of HHV-6 myocarditis among immunocompromised patients, however, the virus’s role in the pathology of acute chronic myocarditis remains poorly defined.

A group of physicians from the University Hospital in Reims, France, have reported a case of fatal HHV-6 myocarditis in an immunocompetent patient (Leveque 2011). Although the initial bloodwork and heart biopsies tested came back negative for the presence of HHV-6 infection, post-mortem frozen tissues showed evidence of chronic HHV-6 infection in regions of the heart that had not been biopsied in the initial screening process. This report demonstrates that HHV-6 can establish a nearly undetectable chronic active myocarditis in the immunocompetent which may eventually result in heart failure and death. The authors emphasize the importance of endomyocardial biopsy and molecular analysis on frozen tissue—as opposed to fixed tissues—as HHV-6 was not detected in either serum or in paraffin fixed tissues of this patient. The antibody titers for HHV-6 were not elevated. Endomyocardial biopsies are not performed for most myocarditis cases in the United States, but are done routinely in Germany and in other European centers.

In addition to the direct association with myocarditis, HHV-6 is also associated with heart complications due to endothelial cell dysfunction. For more information, visit our page on HHV-6 & Endothelial Cell Dysfunction/Arteriopathies.


Key Papers: HHV-6 & Heart Disease

Myocarditis/Cardiomyopathy

Ashrafpoor 2013 Fulminant HHV-6 myocarditis in an immunocompetent adult: role of cardiac MR in a multidisciplinary approach
Hakacova 2013 First therapeutic use of Artesunate in treatment of HHV-6B myocarditis in a child
Magnoni 2012 Molecular study of HHV-6 and HHV-8 involvement in coronary atherosclerosis and coronary instability
Nishimoto 2012 Prolonged sinus tachycardia caused by HHV-6 encephalomyelitis after allogeneic BMT
Leveque 2011 A fatal case of Human Herpesvirus 6 chronic myocarditis in an immunocompetent adult.
Mahrholdt 2006 Presentation, patterns of myocardial damage, and clinical course of viral myocarditis.
Kühl 2005 Viral persistence in the myocardium is associated with progressive cardiac dysfunction.
Ramalho 2011 Human herpes virus 6 causing myocarditis in a fetus: an infectious cause to a congenital heart defect.
Tátrai 2011 The role of viral infections in the development of dilated cardiomyopathy.
Andréoletti 2009 Viral causes of human myocarditis.
Chang 2009 Human herpesvirus 6-related fulminant myocarditis and hepatitis in an immunocompetent adult with fatal outcome.
Bigalke 2007 Human herpesvirus 6 subtype A-associated myocarditis with ‘apical ballooning’.
Bültmann 2005 High prevalence of viral genomes and inflammation in peripartum cardiomyopathy.