P-18 Matrix Metalloproteinases and Late Gadolinium-Enhancement with Cardiovascular Magnetic Resonance in Patients with Dilated Cardiomyopathy

Abstract

Enteroviruses have been implicated in the pathogenesis of idiopathic dilated cardiomyopathy (IDC). Recently, adenovirus and parvovirus have been proposed as etiological agents of IDC. Viral Infection in the myocardium of patients with end-stage IDC was evaluated. Myocardial specimens from 30 American IDC patients, obtained during heart transplants, and from 47 Japanese IDC patients, obtained during partial left ventriculectomy, were analyzed for the presence of viruses. Established RT-PCR or PCR was used to detect genomic sequences of enterovirus, influenza virus, mumps virus, adenovirus, herpes simplex virus, varicellazoster virus, and Epstein-Barr virus. Enteroviral RNA was detected in 7 (23%) of the 30 American patients and in 15 (32%) of the 47 Japanese patients. Sequence analysis revealed that the viruses detected were coxsackieviruses, such as coxsackievirus B3. No genomic sequences of other viruses were detected in the myocardium. A highly sensitive real-time LightCycler PCR assay was developed for the quantification of coxsackieviral genome in the myocardium. The linear dynamic range, spanning from 10 to 1010 copies, can detect viral genome in the myocardium of patients at all stages of the disease process. Low copy number of coxsackieviral RNA was detected in the myocardium of both American and Japanese patients. Conclusion: Low level of coxsackieviral RNA in the myocardium was demonstrated in a significant proportion of patients with end-stage IDC. There was no evidence of infection by other viruses in the myocardium of IDC patients.