IMMUNOLOGIC FINDINGS IN IDIOPATHIC CARDIOMYOPATHY

Thirty-three patients with idiopathic cardiomyopathy were studied for evidence of autoimmune disease. Three additional groups of patients were investigated: 12 with other cardiac diseases; 11 with miscellaneous systemic diseases; 25 normal subjects served as controls. Heart muscle antibodies were found in 4 patients with cardiomyopathy (12 per cent), more often than in controls (4 per cent), but less often than in patients with other cardiac diseases (33 1 3 per cent). None showed evidence of an antinuclear factor. Total serum globulins exceeded 3.5 Gm. per 100 ml. serum in 5 of 33 cardiomyopathy patients. By immunoelectrophoresis, IgA was increased in 9 of 33 cardiomyopathy patients; IgG was elevated in 4 of the 33 patients. Serum complement levels were normal in the cardiomyopathy group; none had a biologic false positive test for syphilis. Although 4 had a positive latex test for the rheumatoid factor, none had a positive sheep cell agglutination test. These results fail to show evidence of autoimmune disease in the majority of our patients with idiopathic cardiomyopathy, and do not support the concept that immune mechanisms are responsible for this disease in the majority of instances. © 1969.