Abstract 10494: The Impact of Complete versus Partial Preservation of the Sub-Valvular Apparatus on Left Ventricular Function in Mitral Valve Replacement

Abstract

Introduction: In mitral valve replacement (MVR), sudden increase in afterload and disruption of the annular-chordal-papillary-left-ventricular wall causes LV dysfunction in the early postoperative period. Preservation of the posterior mitral leaflet apparatus (MVR-P) has a favourable outcome on LV function. However, there is paucity of data on the impact of complete preservation of the sub-valvular apparatus (MVR-C). Objective: We investigated the impact of MVR-P and MVR-C on baseline and 3-months postoperative LV ejection fraction (EF) and global longitudinal strain (GLS). Methods: We retrospectively analysed a cohort of 29 MVR-P and 19 MVR-C patients with complete echo data at our unit, who were operated between 2012-2017. Between-group changes in LVEF and GLS were compared using independent sample T-test. Results: Median age was 59 years (IQR 50-69 years). Baseline LVEF was 58% (51 - 60%). Baseline GLS was -18.4 (-21.2 - -15.5). There were no significant differences between all baseline demographics including age (p=0.45), underlying MV pathology (p=0.1), baseline LVEF (p=0.48) and GLS (p=0.15). There was significantly less worsening of GLS in MVR-C group as compared to the MVR-P group (p=0.023), indicating better preservation of LV function. There was also a lower decrease in LVEF in the MVR-C as compared to the MVR-P group, although the difference was not statistically significant (p=0.23). Conclusion: MVR with complete preservation of the sub-valvular apparatus shows a favourable impact on the longitudinal function of the heart at 3 months. Further studies with larger patient numbers are indicated to investigate the long-term results of this surgical approach.