Impact of preoperative anterior leaflet tethering on the recurrence of ischemic mitral regurgitation and the lack of left ventricular reverse remodeling after restrictive annuloplasty.

Background: The aim of this multicenter study was to investigate the impact of the preoperative anterior mitral leaflet tethering angle, α', on the recurrence of mitral regurgitation (MR) and left ventricular (LV) reverse remodeling (LVRR) after undersized mitral ring annuloplasty.

Methods: The study population consisted of 362 patients, who were divided into two groups by baseline α': group 1, α' < 39.5° (n = 196), and group 2, α' ≥ 39.5° (n = 166). End points were recurrent MR ≥ 2+; LVRR, defined as a reduction in end-systolic volume index > 15%; and LV geometric reverse remodeling, defined as a reduction in systolic sphericity index to a normal value of <0.72 in patients with altered baseline geometry.

Results: MR occurred in 9.6% (n = 19) and 43.3% (n = 72) of the patients in groups 1 and 2, respectively (P < .001). LVRR (85.7% vs 22.2%) at follow-up was higher in group 1 (P < .001). On multivariate regression analysis, α' ≥ 39.5° was a strong predictor of MR recurrence, lack of LV reverse remodeling and lack of LV geometric reverse remodeling (all P values < .001). In contrast, the posterior mitral leaflet tethering angle, β', was not significant (all P values > .05). When we allowed for interactions between α' and other risk factors, this effect occurred also in low-risk subgroups, and it was equivalent or generally attenuated in higher risk patients. There were no significant interactions between α' and any of the covariates (all P values > .05).

Conclusions: Anterior mitral leaflet tethering is a powerful predictor of MR recurrence and lack of LVRR after undersized mitral ring annuloplasty. Evaluation of leaflet tethering should be incorporated into clinical risk assessment and prediction models.