Background and aim of the study: The study aim was to conduct an annual evaluation of plasma levels of C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and antibodies against Chlamydia pneumoniae during a 12-month period following the natural course of aortic valve stenosis (AVS).
Methods: A total of 60 patients with AVS and 14 control subjects underwent echocardiographic examinations at the start of the study period, and again after a 12-month follow up period. Subsequently, the AVS patients were allocated retrospectively to two groups (n = 30 in each) according to their echocardiographic parameters: patients who showed a progressive deterioration of valvular function (PAVS group); and those who showed a lack of such progression (LPAVS group). Plasma concentrations of CRP, TNF-alpha, IL-6, and antichlamydial IgA, IgG, and IgM antibodies were evaluated at the start of the study, and again during the 12th month.
Results: During the study, CRP levels were increased only in the AVS group. TNF-alpha and IgM levels were higher in the AVS group compared to controls, at both the initial visit and the final observation. During the 12-month observation period the TNF-alpha level was increased in the PAVS group, whereas CRP levels in the LPAVS group were decreased. TNF-alpha levels were higher in the PAVS group than the LPAVS group, at both the initial visit and after 12 months; CRP levels did not differ between these groups. In the PAVS group, the IL-6 level was higher after 12 months, but the IgM level was higher at the initial visit. The results of a factorial analysis identified the main factors responsible for the decrease in aortic valve area to be TNF-alpha and CRP.
Conclusion: TNF-alpha, CRP, and IgM antichlamydial antibodies should be further investigated as potential predictive factors for the progression of AVS.