WHAT IS ANTIMYOCARDIAL ANTIBODY TEST?
The antimyocardial antibody is an antibody to an organ-specific antigen in myocardial tissue that causes autoimmune damage to the heart and may be detected in serum before the appearance of clinical symptoms. The myocardial antigenic determinant is also believed to be a characteristic of streptococci because the antibodies may appear in rheumatic fever or after a streptococcal infection. This test uses an indirect immunofluorescence method by treatment of extracts of animal cardiac tissue with the client’s serum and observation for the development of antigen-antibody immune complexes. Positive results are reported in titers of the lowest dilution at which the immune complexes can be detected, and decreasing titers correlate with response to treatment. This test is used in the detection of an autoimmune cause for the above-listed conditions and for monitoring therapeutic response to treatment for the above-listed conditions.