Rheumatic fever and chronic rheumatic heart disease (RHD) remains one of the most important causes of cardiovascular morbidity leading to a major public health problem, especially in developing countries. This was a pilot study to assess the presence of inflammation and expression of adhesion molecules by immunohistochemistry (IHC) in endomyocardial biopsy specimens of patients with chronic RHD.
Endomyocardial biopsy was obtained from 14 patients of chronic RHD with no features of activity clinically. Biopsies were processed for histology and IHC. IHC was carried using monoclonal antibodies against CD3, CD4, CD8, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1.
Histomorphologically, varying degree of interstitial and perivascular fibrosis was seen in all the 13 patients (100%). Mild fibrosis (1+) was seen in five patients (38.5%); moderate interstitial fibrosis (2+) was present in four patients (30.8%).There was no Aschoff nodule or evidence of active myocarditis in any of the biopsy specimens. IMMUNOHISTOCHEMISTRY: Moderate positivity of (2+) and intense positivity of (3+) for intercellular adhesion molecule-1 was seen in 11 and 2 patients, respectively. With vascular cell adhesion molecule-1, four showed mild positivity (1+), and three showed intense positivity (3+). The phenotypic analysis of the inflammatory cells in our study revealed CD8(+) cells in 77%, CD4(+) in 23.1%, and CD3(+) in 38.5% of total patients, which suggests chronicity.
The nonspecific histomorphological changes and increased adhesion molecules expression could be a part of the ventricular remodeling due to the hemodynamic stress by the stenotic or regurgitant lesions of RHD itself.