STUDY OBJECTIVES: This study was performed to assess the changes in pulmonary function after a successful percutaneous balloon mitral valvotomy (PBMV) in 23 consecutive patients with symptomatic mitral stenosis. METHODS AND RESULTS: Lung function preprocedure and postprocedure were evaluated by spirometric flow, static pulmonary volumes, and diffusion capacity of the lung for carbon monoxide (DLCO). At baseline, a reduction in small airways flow (maximal expiratory flow at 50% of vital capacity, 70 +/- 29% of predicted value; maximal expiratory flow at 25% of vital capacity, 55 +/- 26% of predicted value) and an increase in DLCO (118 +/- 29%) and Krough Index (KCO; 123 +/- 29% of predicted value) were observed. PBMV caused an improvement in hemodynamic parameters with an increase in mitral valve area (from 1.0 +/- 0.3 to 1.9 +/- 0.5 cm(2); p < 0.001) and a decrease in left atrial pressure (from 17 +/- 3 to 12 +/- 5 mm Hg; p < 0.001). These changes were associated with a significant increase in FVC (from 2.8 +/- 0.84 to 2.9 +/- 0.80 L; p < 0.05) and in FEV(1) (from 2.2 +/- 0.72 to 2.3 +/- 0.68 L; p < 0.05). A decrease in DLCO was observed after PBMV (from 26.7 +/- 7 to 22.5 +/- 5.4 mL/min/mm Hg; p < 0.001; and KCO, from 6.2 +/- 1.4 to 5.2 +/- 1.2 mL/min/mm Hg/L; p < 0.001). No significant changes in small airways flow were detected, suggesting only a partial improvement in pulmonary congestion. CONCLUSION: We conclude that the initial impairment of lung function in patients with symptomatic mitral stenosis is only partially ameliorated by PBMV.
STUDY OBJECTIVES: This study was performed to assess the changes in pulmonary function after a successful percutaneous balloon mitral valvotomy (PBMV) in 23 consecutive patients with symptomatic mitral stenosis. METHODS AND RESULTS: Lung function preprocedure and postprocedure were evaluated by spirometric flow, static pulmonary volumes, and diffusion capacity of the lung for carbon monoxide (DLCO). At baseline, a reduction in small airways flow (maximal expiratory flow at 50% of vital capacity, 70 +/- 29% of predicted value; maximal expiratory flow at 25% of vital capacity, 55 +/- 26% of predicted value) and an increase in DLCO (118 +/- 29%) and Krough Index (KCO; 123 +/- 29% of predicted value) were observed. PBMV caused an improvement in hemodynamic parameters with an increase in mitral valve area (from 1.0 +/- 0.3 to 1.9 +/- 0.5 cm(2); p < 0.001) and a decrease in left atrial pressure (from 17 +/- 3 to 12 +/- 5 mm Hg; p < 0.001). These changes were associated with a significant increase in FVC (from 2.8 +/- 0.84 to 2.9 +/- 0.80 L; p < 0.05) and in FEV(1) (from 2.2 +/- 0.72 to 2.3 +/- 0.68 L; p < 0.05). A decrease in DLCO was observed after PBMV (from 26.7 +/- 7 to 22.5 +/- 5.4 mL/min/mm Hg; p < 0.001; and KCO, from 6.2 +/- 1.4 to 5.2 +/- 1.2 mL/min/mm Hg/L; p < 0.001). No significant changes in small airways flow were detected, suggesting only a partial improvement in pulmonary congestion. CONCLUSION: We conclude that the initial impairment of lung function in patients with symptomatic mitral stenosis is only partially ameliorated by PBMV.