[Primary acute myocarditis. A 10- years institutional experience]

Acute myocarditis (AM) is associated with viral infections: Coxsackie and ECHOviruses among others. Autoimmunity has been proposed as a pathogenic mechanism. Benefit of classic immunosuppression (prednisone-azathioprine) or immunomodulation (monomeric-human IgG) is still uncertain.

To review incidence and clinical approach to AM at a Cardiology referral center.

A 10-yeard period (1992-2003) is reviewed. A standard questionary was applied to 49 consecutive patients referred by clinicians with a diagnosis of AM.

AM was found in 17 women and 32 men, median age 24 and 28 years, respectively. They presented heart failure with dyspnea/ortopnea (70-47%), peripheral edema/jugular vein plethora (41-37%), chest pain, and tachycardia (50%), NYHA functional class was Ill-IV in 22. The EKG showed sinus tachycardia or conduction defects. Transthoracic echocardiograms in 47 cases showed EF (mean) of 41% with enlarged left ventricle diameter. Antivirus antibodies were present in 54% of those cases studied, Coxsackie or ECHOvirus were identified through a serologic assay. Twenty-nine (61%) of our cases developed dilated cardiomyopathy, three patients died. It is not possible to reach a conclusion regard to immunomodulation therapy, because it was applied to only 12 patients.

At the Instituto Nacional de Cardiología "I. Chávez", AM depicts an incidence of 1/1,000 patients a year. It is necessary to standardize the clinical approach for diagnosis and treatment, progression to dilated cardiomyopathy and death during acute stage occurs in two-thirds of our patients.