Lung Function and Severity of Mitral Stenosis

Objective: To correlate the degree of severity in patients with rheumatic mitral stenosis to pulmonary function data and to their respiratory symptoms. Methods: Pulmonary function and the MCR questionnaire on respiratory symptoms were made in 43 patients with simple mitral stenosis (SMS), and 79 patients with advanced mitral stenosis scheduled for valve replacement surgery (MVR). Results: All the patients in the two groups had restrictive and obstructive patterns. They had reduced forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), peak expiratory flow rate, maximal flow after exhalation of 75, 50 and 25% of FVC and single-breath carbon monoxide diffusing capacity (DLCO) and increased total airway resistance, resistance during expiration, and residual volume (RV). The SMS group tended toward more normal values. The MVR group had lower values for all the parameters, specially FVC, FEV1, DLCO and higher RV. The MVR group had a significantly higher prevalence of cough, phlegm and acute chest illness than the SMS group. Conclusion: The study confirmed the restrictive and obstructive pattern of pulmonary dysfunction in patients with rheumatic mitral stenosis which related with the severity of mitral stenosis and with respiratory symptoms.