Echocardiographic features of atrial myocarditis with giant cells: a case report.

We report a case of restrictive cardiomyopathy in which a distinct endothelial thickening of the atrial wall and pulmonary vein orifices was noted on transesophageal echocardiography. Echocardiographically guided endomyocardial biopsy of the thickening revealed an inflammatory infiltrate that was rich in giant cells and provided important clues about an underlying immune mechanism for the pathogenesis. Positive results from the antineutrophil cytoplasmic autoantibody assay supported the diagnosis of Wegener's granulomatosis. After immunosuppressive therapy, the endomyocardial thickening completely resolved, but the restrictive cardiomyopathy did not reverse.