Percutaneous balloon mitral valvuloplasty using the Inoue balloon: analysis of echocardiographic and other variables related to immediate outcome

To determine whether the mitral valve morphology influences the results of percutaneous balloon mitral valvuloplasty for mitral stenosis, two-dimensio nal echocardiography was performed before valvuloplasty in 126 patients (me an age 25.5+/-9.4 years) and in 30 normal controls. The 2D echocardiographi c features of mitral valve leaflets: thickness, length and motion; diastoli c mitral valvular excursion; chordal length; mitral annular diameter; subva lvular distance ratio; distance between mid mitral annulus to left ventricu lar apex, base and tip of papillary muscle and effective balloon dilating a rea, effective balloon dilating area/body surface area and effective balloo n dilating diameter/mitral annular diameter were then correlated to the imm ediate post-valvuloplasty mitral valve area. For the total patients populat ion, post-valvuloplasty valve area increased from 0.67+/-0.17 to 2.1+/-0.86 cm(2) (P<0.0001), mean transmitral diastolic gradient decreased from 24.5/-9.0 to 6.0+/-3.0 mmHg (P<0.0001), mean left atrial pressure decreased fro m 29.7+/-6.2 to 12.7+/-4.8 mmHg (P<0.0001), mean pulmonary artery pressure decreased from 44.8+/-14.2 to 25.4+/-9.5 mmHg (P<0.0001) and cardiac index increased from 2.7+/-0.38 to 3.1+/-0.55 l/min/m(2) (P<0.0001). The patients were divided into three groups on the basis of post-valvuloplasty mitral v alve area. Group I had valve area <1.5 cm(2), group II had valve area from 1.5 to 1.9 cm(2) and group III had valve area greater than or equal to 2.0 cm(2). On comparison, no statistically significant difference was found in any of the echocardiographic variables in the three groups. On univariate, multivariate, multiple regression and discriminate function analysis, none of the variables were found to have significant influence on immediate resu lt of valvuloplasty. There was no significant difference in the incidence o f mitral regurgitation in any of the three groups. We conclude that the ext ent of mitral valvular and subvalvular deformity do not have a significant effect on the immediate outcome of mitral valvuloplasty using the Inoue bal loon and it can be successfully performed in patients with severe subvalvul ar fibrosis. Unique balloon geometry and stepwise balloon sizing may explai n these acceptable immediate results in severely deformed valves. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.