Clinical and echocardiographic differences in three different etiologies of severe mitral stenosis.

Background: In our institute, the causes of mitral stenosis (MS) are generally categorized into three main etiologies-rheumatic MS (RMS), degenerative MS with annular and leaflet calcification, and post-clip MS as a consequence of transcatheter mitral valve repair with clips for treating mitral regurgitation. However, clinical differences among the three etiologies are uncertain.

Methods: We retrospectively assessed 293 consecutive patients (53 with RMS, 118 with degenerative MS, and 122 with post-clip MS) who had a three-dimensional (3D) transesophageal echocardiography (TEE) derived mitral valve orifice area (MVA) of ≤1.5 cm , and a mean transmitral pressure gradient of ≥5 mmHg on transthoracic echocardiography.

Results: Although there was no difference in 3D-TEE-derived MVA among the three groups, patients with post-clip MS had a significantly lower mean transmitral pressure gradient compared to those with either of the other two types of MS (10.8 ([7.9-15.2] mmHg vs. 9.6 [7.3-12.5] mmHg vs. 6.9 [6.0-9.2] mmHg; p < .001). Patients with RMS had a higher prevalence of dyspnea. The independent determinants of dyspnea were pressure half time in RMS, 3D-TEE-derived MVA and estimated right atrial pressure in degenerative MS, and left ventricle ejection fraction in post-clip MS.

Conclusions: Patients with post-clip MS had the lowest mean transmitral pressure gradient, and patients with RMS had the highest prevalence of dyspnea, despite having a similar 3D-TEE-derived MVA. The determinants of dyspnea were different among the three etiologies of MS.