心血管疾患と診断

The Immediate and Short Term Impact of Successful Percutaneous Transvenous Mitral Commissurotomy on Right Ventricular Function

Abstract

Santosh Kumar C, Rajasekhar D, Vanajakshamma V and Boochi Babu M

Objectives: The purpose of this study was to evaluate the immediate and short term follow up impact of Percutaneous Transvenous Mitral Commissurotomy (PTMC) on Right Ventricular (RV) function using twodimensional and tissue Doppler echocardiographic indices.

Background: In patients with Mitral Stenosis (MS) RV function may be affected due to myocardial and hemodynamic factors. Previous studies using echocardiography have shown discordant results as regards to improvement of RV function immediately after PTMC. Only few studies have evaluated RV function at 6 months follow up.

Methods: A total of 90 patients with severe symptomatic MS, all in sinus rhythm, who got admitted for PTMC to author’s institute, were prospectively enrolled. RV function was evaluated by conventional and Tissue Doppler Imaging (TDI) echocardiography before, 48 hours after PTMC, and at 6 months follow up. Results: All patients underwent successful PTMC. The mitral valve area was significantly increased (0.80 ± 0.13 cm2 versus 1.73 ± 0.14 cm2, p=0.0001) immediately after PTMC, while the mean transmitral gradient (21.6 ± 8.0 mm Hg versus 5.9 ± 1.6 mm Hg, p < 0.0001) and systolic pulmonary artery pressure (52.3 ± 23.4 mm Hg versus 41.7 ± 16.9 mm Hg, p < 0.0001) were significantly decreased. There was significant improvement in RV function immediately after PTMC (RV outflow tract fractional shortening (RVOTfs): 54.1 ± 8.7% versus 70.4 ± 5.0%, p < 0.001, Tricuspid Annular Plane Systolic Excursion (TAPSE): 16.0 ± 1.5 mm versus 18.6 ± 1.7 mm, p < 0.0001, TEI INDEX: 0.51 ± 0.04 to 0.34 ± 0.04, p < 0.001). Myocardial velocities measured at lateral tricuspid annulus were not improved significantly immediately after PTMC but improved significantly at 6 months follow up (Myocardial velocity during isovolumic contraction (IVCv); 10.2 ± 0.6 cm/s to 12.0 ± 1.3 cm/s, p < 0.001, systolic myocardial velocity (Sv): 11.7 ± 0.9 cm/s to 13.2 ± 0.9 cm/s , p < 0.001 , myocardial acceleration during isovolumic contraction(IVA): 3.0 ± 0.5 cm/s2 to 3.9 ± 0.3 cm/s2 , p < 0.001).

Conclusion: Immediately after successful PTMC, significant improvement in RV function was observed. TDI myocardial velocities and IVA showed gradual improvement in RV function at 6 months follow up. Prognostic value and clinical significance of this improvement deserve further investigation.