Immunohistochemical characterization of Aschoff nodules and endomyocardial inflammatory infiltrates in resected left atrial appendages.

Presence of Aschoff nodules and other chronic inflammatory cells in the left atrial appendage even in the absence of rheumatic activity has been reported in a high percentage of patients with chronic rheumatic valvular heart disease. This study was conducted on 37 left atrial appendages resected at the time of closed mitral valvotomy. Aschoff nodules were present in 61.2 percent of resected appendages, positivity being 71.4 percent in the age group of 20 years of less and 53.3 percent in patients more than 20 years of age. The histological findings did not change significantly in the presence of activity. The frequency of Aschoff nodules and chronic inflammatory cells and their subtypes also did not show any correlation with age, sex, duration of symptoms or severity of mitral stenosis.