An analysis of the relationship between severity of rheumatic mitral stenosis and serum alpha-1 antitrypsin levels

Background and Aim: Rheumatic heart valve disease continues to be a serious public health problem in our country and developing countries. However pathophysiologic mechanizm has not yet been clarified. The main function of alpha-1 antitrypsin is to protect tissues against the enzyme neutrophil elastase. The severity of tissue injury is proportional to the unbalanced protease activity. In our study, alpha-1 antitrypsin levels were examined in patients with mild, moderate and severe mitral stenosis. Material and Method: 46 patients with severe, 63 patients with moderate,111 patients with mild rheumatic mitral stenosis(MS) and 100 healthy participants took part in this study. After transthoracic echocardiography was performed, diagnoses were confirmed by transoesophageal echocardiography. Patients mitral stenosis were divided into three groups according to the severity based on valve area; ≤1 cm2 as severe, 1.1-1.5 cm2 moderate and ≥1.6 cm2 mild. Serum alpha 1-antitrypsin levels were measured. Results: There were 220 patients (56 male and 164 female) in the control group 100 healthy controls (21 male and 79 female). The mean age of patients and controls were were 43,1±13,6 and 42,9±7,9 years respectively. Among patients 46 had severe (21%), 63 had moderate (29%) and 111 had mild mitral stenosis (50%). Alpha-1 antitrypsin levels were similar in both severe MS group and healthy controls. There was a significant difference in alpha-1 antitrypsin levels between moderate MS patients and healthy controls (p:0.016). The most robust association was observed between mild MS and healthy controls (1.52±0.31 vs 1.36±0.17 p<0.001). Conclusion: Patients with mild and moderate mitral stenosis had significantly higher alpha-1 antitrypsin levels compared to healthy controls. The association was not significant for patients with severe mitral stenosis. All these results suggest that elevated serum alpha-1 antitrypsin levels could play a protective role in the progression of rheumatic mitral stenosis.