Echocardiographic predictors of operative outcome for transapical off-pump mitral valve repair with neochord implantation

Abstract Introduction Transapical off-pump mitral valve repair with artificial neochord implantation (TOP-MINI) is safe and effective for the treatment of primary mitral regurgitation12, however, the current literature regarding echocardiographic criteria prior to the procedure is scarce. Objective To identify preoperative echocardiographic predictors of technical success after TOP-MINI for severe primary mitral regurgitation. Methods All consecutive patients who underwent TOP-MINI for severe primary mitral regurgitation from 2017 to 2022 were included. Preoperative echocardiographic evaluation included transthoracic and transesophageal echocardiography. Transesophageal evaluation included 2D measurements of mitral valve annulus, mitral leaflets, flail gap, and 3D mitral valve reconstruction among others, the leaflet-to-annulus index was estimated in all patients. Mitral valve morphology was classified as: Type A (Central posterior leaflet prolapse/flail) or non-Type A (Type B: posterior multisegment involvement; type C: anterior leaflet prolapse; type D: paracommissural or calcified leaflet). Technical success was defined according to the Mitral Valve Academic Research Consortium criteria. Independent echocardiographic predictors for the primary outcome were identified using a multivariate logistic regression model. Results Fifty-five patients were included. Mean age was 66.7 years (SD 12.9). Technical success with MR <2+ was achieved in 48 (87.27%) patients. Significant predictors for technical success were the leaflet-to-annulus index (OR 1.09; p=0.012; 95% CI: 1.02–1.15), with an optimal cutoff value of 1.26 (sensitivity 73.3%, specificity 85.7%); and a non-type A valve morphology (OR 0.04; p=0.024; 95% CI: 0.01–0.65). The model showed good discrimination (AUC = 0.92) and calibration (Hosmer-Lemeshov p=0.21). Conclusion A thorough preoperative echocardiographic evaluation is key to improve outcomes in TOP-MINI. In this study, a leaflet-to-annulus index >1.26 was associated with technical success, whether a non-type A valve morphology was associated with technical failure. These parameters could help to identify proper candidates for this technique. Funding Acknowledgement Type of funding sources: None.