Early- and mid-term effects of percutaneous mitral balloon valvuloplasty on left atrial mechanical functions in mitral stenosis

OBJECTIVES: The aim of the study was to evaluate left atrial (LA) mechanical functions in MS before and after percutaneous mitral balloon valvuloplasty (PMBV) and to follow it up in short- and mid-term. STUDY DESIGN: We carried out a prospective study of 49 patients with critical mitral stenosis (MS) who had normal sinus rhythm. LA mechanical functions were evaluated before and 24-48 h, 3 months, and 1 year after PMBV, which included LA passive emptying volume (LAPEV), LA active emptying volume (LAAEV), LA total emptying volume (LATEV), LA passive emptying fraction (LAPEF), LA active emptying fraction (LAAEF), LA total emptying fraction (LATEF), and conduit volume. RESULTS: The transthoracic echocardiography parameters of the MS patients before and 24-48 h, 3 months, and 1 year after PMBV were as follows: (a) mitral valve area 1.1 cm² (0.9-1.6); 2.2 cm² (1.8-2.8) (p<0.001); 2.2 cm² (1.7-2.9) (NS); 2.1 cm² (1.8-2.7) (p<0.001); (b) LAPEV 13 ml/m² (9-27); 11 ml/m² (8-19) (p<0.001); 10 ml/m² (7-19) (p<0.001); 10 ml/m² (6-18) (p<0.001); (c) LATEV 26 ml/m² (19-50); 21 ml/m² (16-40) (p<0.001); 20 ml/m² (15-36) (p<0.001); 19 ml/m² (15-34) (p<0.001); (d) Conduit volume 30 ml/m² (22-44); 33 ml/m² (26-46) (p<0.001); 34 ml/m² (30-42) (p<0.001); 36 ml/m² (31-42) (p<0.001), respectively. However, LAAEV, LAPEF, LAAEF, and LATEF were not altered after PMBV. CONCLUSION: The findings of this study demonstrated an improvement of LA mechanical functions, which continued to improve for 1 year, after successful treatment of MS by PMBV.