Objective: To compare the immediate outcome of percutaneous mitral valvotomy (PMV)using the metallic mitral commissurotome and the Inoue balloon.Design: Randomized single-blind controlled experimental trial.Setting: Tertiary care, medical school hospital.Participants: Sixty adult patients with moderate to severe mitral stenosis who had clinical indications for PMV.Intervention: The patients were randomized to underwent PMV with either the new metallic device or the Inoue balloon. The echocardiography assessing the mitral valve area and other variables post PMV was performed and collected by a blinded cardiologist one day after the procedure.Main outcome measures: Success of PMV, define as post-valvotomy mitral valve area (MVA) measured by 2-D echocardiography is more than or equal to 1.5 cm[superscript 2] and mitral regurgitation (MR) severity Sellers' grade < 2.Results: The success rate was not different between the metallic commissurotome and the Inoue balloon (37% vs. 37%, p 0.5). The post-PMV MVA in the Inoue group was 1.38 +- 0.28 cm2 vs. 1.47 +- 0.33 cm[superscript 2] in the metallic commissurotome (p 0.26). Procedural failure in the Inoue group was mainly (18 patients) from post-PMV MVA < 1.5 cm[superscript 2] and 1 patient developed severe mitral regurgitation. Whereas causes of failure in the metallic commissurotome were crossover in 4 patients, 12 post-PMV MVA < 1.5 cm[superscript 2],1 had severe mitral regurgitation and 2 had cardiac tamponade. The same metallic commissurotome could be used in all 30 patients. On the other hand, 23 Inoue balloon were used in the 30 patients. Conclusion: The success rate of PMV is not different between metallic commissurotome and Inoue balloon. Complications with metallic commissurtome tend to be more serious. However, the cost effectiveness is better with the metallic commissurotome
