Three-dimensional echocardiographic assessment before and after percutaneous transvenous mitral commissurotomy in patients with rheumatic mitral stenosis.

Background And Aim Of The Study: Real-time three-dimensional transthoracic echocardiography (RT3DE) is a relatively recent imaging technique that provides excellent image quality of the mitral valve. It has been suggested that this new echocardiographic modality, which allows a precise cross-section of the mitral orifice at the tips of the leaflets with correct plane orientation, may provide a more accurate assessment of rheumatic mitral stenosis (MS) than two-dimensional echocardiography (2DE), before and after percutaneous transvenous mitral commissurotomy (PTMC).

Methods: A total of 50 patients with symptomatic mitral stenosis who underwent PTMC was evaluated prospectively. Patients in all age groups, with evidence of severe MS admitted to the authors' institution, in whom PTMC was feasible were included.

Results: A good valve opening was observed in 45 patients (90%). The mitral valve area (MVA) assessed before PTMC with 3DE (3D-MVA) correlated well with that assessed with 2DE (2D-MVA) (0.85 +/- 0.12 cm2 versus 0.86 +/- 0.13 cm2, p < 0.001); the mean difference between methods was small (0.01 +/- 0.11 cm2) and correlation excellent (r = 0.64, p < 0.001). After PTMC, values of 3D-MVA did not differ from, and correlated well with, values of 2D-MVA (1.79 +/- 0.20 cm2 versus 1.74 +/- 0.18 cm2, p = 0.006); the mean difference between methods was small (0.05 +/- 0.02 cm2) and correlation excellent (r = 0.76, p = 0.0001). Before PTMC, Bland-Altman analysis showed a good agreement between methods (mean difference -0.01 +/- 0.11 cm2, lower limit -0.24, upper limit 0.22). After PTMC, Bland-Altman analysis showed a good agreement between methods (mean difference -0.05 +/- 0.13 cm2, lower limit -0.3, upper limit 0.2). Evaluation of the commissural opening after PTMC, using RT3DE, showed that excellent commissural evaluation was possible in all patients. Compared with RT3DE, an underestimation of the degree of commissural fusion using 2DE was observed in 32%, with a weak agreement between methods.

Conclusion: RT3DE provided accurate measurements of MVA, similar to 2D planimetry. RT3DE also improved the description of valvular anatomy and provided a unique assessment of the extent of commissural splitting.