Common viruses linked to severity of heart condition
SOURCE: Journal of the American College of Cardiology 2000;36:1920-1926

NEW YORK, Nov 14 (Reuters Health) - It has long been suspected that common viruses can sometimes cause dilated cardiomyopathy, an often-fatal condition in which the heart muscle stretches out and becomes too weak to pump blood effectively. Now, Japanese researchers think they have strong evidence that a certain group of viruses--known as coxsackie B viruses--may be to blame for severe cases of dilated cardiomyopathy virus. Any of various simple submicroscopic parasites of plants, animals, and bacteria that often cause disease and that consist essentially of a core of RNA or DNA surrounded by a protein coat. Unable to replicate without a host cell, viruses are typically not considered living organisms.

Cardio-Heart: cardiovascular. my·op·a·thy
A disease of muscle or muscle tissue. In a study of 26 patients treated with surgery for the condition, sophisticated viral detection techniques determined that 9 patients were infected with coxsackie B viruses. The researchers from Osaka Medical College in Takatsuki and Shonan Kamakura General Hospital in Kamakura checked for eight other virus types thought to be associated with the heart condition, but found none of them. In seven of the patients infected with coxsackie virus, the investigators found evidence that the virus was actively replicating. When they checked the heart tissue of 21 people who died of other causes, none contained the viruses. Patients infected with the viruses had a worse prognosis, the report indicates. Six of the nine patients with the virus (67%) died within 6 months of surgery. Mortality was higher still in the patients whose hearts harbored actively replicating viruses. But only 4 of the 17 patients without the virus (24%) had died within a year of the surgery. "Considering these findings, an antiviral agent to coxsackie B virus should be used for the management of this disease," the authors write in the November 15th issue of the Journal of the American College of Cardiology. Coxsackie viruses take their name from the upstate New York town where they were first identified in 1948. Infection with these viruses is typically mild, although they can cause more severe illness including inflammation of the heart in newborns. A connection between dilated cardiomyopathy and enteroviruses, the family of viruses to which coxsackie viruses belong, has long been suspected, but evidence has been equivocal. en·ter·o·vi·rus Any of a subgroup of picornaviruses, including polioviruses, coxsackieviruses, and echoviruses, that infect the gastrointestinal tract and often spread to other areas of the body, especially the nervous system.