Learning curve of the Inoue technique of percutaneous mitral balloon valvuloplasty.

There is controversy as to whether the double-balloon or the Inoue technique of percutaneous mitral balloon valvuloplasty (PMBV) provides superior immediate and long-term results. This study was undertaken to analyze the effect of the learning curve of the Inoue technique of PMBV in the immediate and long-term outcome of PMBV. The learning curve of Inoue PMBV was analyzed in 233 Inoue PMBVs divided into 2 groups: "early experience" (n = 100) and "late experience" (n = 133). The results of the overall Inoue technique were compared with those of 659 PMBVs performed with the double-balloon technique. Baseline clinical and morphologic characteristics between early and late experience Inoue groups were similar. Post-PMBV mitral valve area (1.89 +/- 0.56 vs 1.69 +/- 0.57 cm(2); p = 0.008) and success rate (60% vs 75.9%; p = 0.009) were significantly higher in the late experience Inoue group. Furthermore, there was a trend for less incidence of severe post-PMBV mitral regurgitation > or = 3+ in the late experience group (6.8% vs 12%; p = 0.16). Although the post-PMBV mitral valve area was larger with the double-balloon technique (1.94 +/- 0.72 vs 1.81 +/- 0.58 cm(2); p = 0.01), the success rate (71.3% vs 69.1%; p = NS), incidence of > or = 3+ mitral regurgitation (9% vs 9%), in-hospital complications, and long-term and event-free survival were similar with both techniques. In conclusion, there is a significant learning curve of the Inoue technique of PMBV. Both the Inoue and the double-balloon techniques are equally effective techniques of PMBV because they resulted in similar immediate success, in-hospital adverse events, and long-term and event-free survival.