Abstract 3553: Changes in Mitral Valve Configuration After Undersized Mitral Annuloplasty and Papillary Muscle Imbrication in Functional Mitral Regurgitation With Severe Leaflet Tethering
Background: Undersized mitral annuloplasty (UMAP) has become the standard surgical procedure to relieve functional mitral regurgitation (FMR). However, residual/recurrent MR is observed in 30% of patients after UMAP. We have utilized papillary muscle imbrication (PMI), in addition to UMAP. In this study, we evaluated the configuration of mitral valve and subvalvular apparatus before and after UMAP and PMI.
Methods: Of 70 patients with FMR (moderate to severe) due to dilated cardiomyopathy since 2004, we studied 21 patients (mean age 62+/−5 years, ejection fraction 24+/−9%) who underwent UMAP combined with adjunctive PMI. Each underwent diagnostic cardiac magnetic resonance imaging (CMR) examinations before and early after surgery. Annular antero-septal diameter, tenting height, tenting area and inter-papillary muscles distance at end-systole were quantified by CMR (Figure⇓: upper).
Results: Annular antero-septal diameter, tenting height, tenting area and inter-papillary muscles distance were significantly decreased (35+/−3 to 23+/−2 mm, 13+/−2 to 8+/−3 mm, 280+/−70 to 90+/−40 mm2 and 43+/−10 to 37+/−6 mm: respectively, p<0.05) (Figure⇓: lower). There was a significant correlation between decrease in inter-papillary muscles distance and decrease in tenting height (R2=0.66, p<0.01).
Conclusion: Quantitative description of mitral valve configuration using CMR demonstrated that combined UMAP and PMI improved leaflet tethering, with decreasing directly inter-papillary muscles distance and thereby decreasing tenting height.