Chronic viral cardiomyopathy is a disease where the cardiac muscle is attacked by a virus and this may result in a reduction in the output of the heart (pump function) thereby causing complaints such as chest pain, shortness of breath and palpitations.

Betaferon (interferon beta-1b) is marketed for the treatment of Multiple Sclerosis already, but until now, it has not been proven whether it is also effective in patients with chronic viral myocardial disease.

This study will be conducted to examine the efficacy and safety of Betaferon in patients with this disease. The aim of the treatment is to eliminate the virus from the heart so that the heart function and clinical status can gradually improve.

The study has previously been posted by Schering AG, Germany. Schering AG, Germany has been renamed to Bayer Schering Pharma AG, Germany.

Bayer Schering Pharma AG, Germany is the sponsor of the trial.

Inclusion Criteria:

• Unexplained heart with evidence of Adeno-, Entero- and/or Parvoviruses which must be identified directly in the heart tissue
• Being in a chronic (at least 6 month after the onset of clinical symptoms) and stable phase of the disease
• Impaired cardiac function

Exclusion Criteria:

• Severe (decompensated) or acute heart failure.
• Any other disease which could better explain the patient's clinical symptoms
• Any other severe and/or malignant disease.
• Suffering from convulsions, depression or suicidal ideas judged by a physician
• Serious viral or bacterial infections during the last weeks
• Pregnancy or lactation