Three-Dimensional Imaging of Pannus Overgrowth after Mitral Valve Repair

Structural analysis of the mitral valve in rheumatic and degenerative mitral valve diseases: implications for annuloplasty selection

BACKGROUND

Mitral valve (MV) repair has been recommended for MV diseases. Good repair requires a full understanding of the three-dimensional (3D) structure of the MV, however, currently little is known about the 3D structure of the rheumatic MV.

METHODS

A total of 82 cases underwent 3DTEE. Of these, 41 patients with rheumatic valvular disease (RVD) were studied intraoperatively (17 had severe mitral stenosis, 8 had severe mitral regurgitation, 16 had severe mitral stenosis coupled with regurgitation). There were 19 patients with degenerative MV disease (mitral valve prolapse [MVP] with severe regurgitation) and 22 cases with normal MV served as control subjects (CS).

RESULTS

Compared with CS, the anteroposterior diameter, anterolateral posteromedial, annulus circumference, and annulus area of both pathological groups, i.e., the RVD and MVP groups, were understandably greater. Though the sphericity index was greater in the RVD group vis-à-vis CS, the MVP group had nearly the same sphericity index as CS. The mitral annulus of patients with RVD tended to be round. Annular unsaddling, defined as annular height to commissural width ratio (an indicator of saddle degree) less than 15%, was significantly more prevalent in the group with degenerative MV disease. Automatic dynamic analysis revealed that the parameters of annular maximum displacement and annulus area fraction (two-dimensional) were considerably decreased in the RVD group.

CONCLUSIONS

Annular unsaddling was significantly more prevalent in the degenerative MV disease group. The mitral annulus of patients with RVD tended to be round and stiff.

Mitral Valve Repair for Pure Mitral Regurgitation Followed Years Later by Mitral Valve Replacement for Mitral Stenosis

We describe herein 2 patients who developed severe mitral stenosis (MS) approximately two decades after a mitral valve repair operation for pure mitral regurgitation (MR) secondary to mitral valve prolapse. This report's purpose is to point out that use of a circumferential mitral annular ring during the repair has the potential to produce a transmitral pressure gradient just like that occurring after mitral valve replacement utilizing a mechanical prosthesis or a bioprosthesis in the mitral position.

Mitral Valve Stenosis after Open Repair Surgery for Non-rheumatic Mitral Valve Regurgitation: A Review

Mitral stenosis (MS) after mitral valve (MV) repair is a slowly progressive condition, usually detected many years after the index MV surgery. It is defined as a mean transmitral pressure gradient (TMPG) >5 mmHg or a mitral valve area (MVA) <1.5 cm(2). Pannus formation around the mitral annulus or extending to the mitral leaflets is suggested as the main mechanism for developing delayed MS after MV repair. On the other hand, early stenosis is thought to be a direct result of an undersized annuloplasty ring. Furthermore, in MS following ischemic mitral regurgitation (MR) repair, subvalvular tethering is the hypothesized pathophysiology. MS after MV repair has an incidence of 9-54%. Several factors have been associated with a higher risk for developing MS after MV repair, including the use of flexible Duran annuloplasty rings versus rigid Carpentier-Edwards rings, complete annuloplasty rings versus partial bands, small versus large anterior leaflet opening angle, and anterior leaflet tip opening length. Intraoperative echocardiography can measure the anterior leaflet opening angle, the anterior leaflet tip opening dimension, the MVA and the mean TMPG, and may help identify patients at risk for developing MS after MV repair.