An intense mononuclear cell infiltrate in the myocardium consisted entirely of T cells without identifiable B cells. These two herpesviruses, EBV and HCMV, are the cardinal etiologic agents of the unified hypothesis proposed here. Productive whole-virus herpesvirus, EBV or HCMV, infection is accompanied by lysis of infected cells. In latent infection, on the other hand, complete infectious virus is not produced, and host-cell survival continues. In persistent infection, varying low levels of infectious virus, latent virus, and intermittent reactivation may occur simultaneously.
Productive infection is associated with cellular necrosis and a subsequent inflammatory response.
Latent persistent infection may be associated with little inflammation or morphologic changes but may lead to only biochemical aberrations and degenerative cellular functions. Hypertensive vascular disease, electrolyte abnormalities, and coronary artery disease may produce similar oscillating abnormal T-waves, but CFS patients are young, formerly vigorous people who typically do not have these chronic diseases. We have performed right ventricular endomyocardial biopsies in CFS patients. Infectious HCMV is not found in the heart, peripheral blood, or urine of this HCMV CFS subset of patients. The evidence appears conclusive that CFS is a major, newly discovered cardiomyopathy.