Abstract 16308: Comparison of Myocardial Mechanics Post Mitral Valve Repair With Leaflet Preservation vs. Leaflet Resection: A Sub-Analysis of the Randomized CAMRA CardioLink-2 Trial

Abstract

Introduction: Prior studies comparing leaflet resection vs. leaflet preservation for surgical repair of mitral regurgitation (MR) caused by prolapse focus predominantly on measurement of left ventricular ejection fraction. This study aims to evaluate subclinical differences in myocardial mechanics pre- mitral valve (MV) repair, immediately after, and 1-year post-repair, as well as compare differences between leaflet resection and preservation strategies. Methods: 104 patients were randomly assigned to the resection or preservation group for surgical treatment of posterior leaflet prolapse in the Canadian Mitral Research Alliance CardioLink-2 study. Speckle-tracking echocardiography was performed at baseline (pre-repair), immediately post-repair, and 1 year post-repair. Global longitudinal strain (GLS) was compared at the three timepoints, as well as between leaflet preservation and resection groups using descriptive statistics. Results: The mean age of the participants was 65 ± 10 years, and 83% were male. The mean GLS pre-MV repair was -19.6 ± 5.4, and did not differ between the leaflet resection and leaflet preservation groups. The mean GLS dropped to -12.8 ± 4.7 immediately post-repair (p= 0.001 compared to pre-repair). The GLS immediately post-repair was slightly lower in the leaflet resection vs. preservation group (-11.8 ± 4.9 vs. -14.2 ± 3.3, p=0.04). At 1 year post-repair, the mean GLS improved to -16 ± 4, but remained below pre-repair values (p=0.001 compared to immediate post-repair, p=0.03 compared to pre-repair values). At 1-year follow-up, there were no differences in GLS between the leaflet resection and preservation groups. Conclusion: The leaflet preservation and resection techniques for surgical repair of MR have similar effects on myocardial mechanics 1-year post-repair. MV repair is associated with an immediate reduction in myocardial strain, with only partial recovery in the first year post-MV repair. Further studies are needed to determine whether myocardial strain continues to improve beyond the first year post-repair to baseline levels.