Background: This study was performed to determine whether strain can supplement the ability of left ventricular (LV) ejection fraction (LVEF) to predict postoperative ventricular dysfunction in patients undergoing mitral valve surgery for degenerative mitral regurgitation (DMR). Methods: From 2004 to 2017, 520 patients with an LVEF of 60% or more underwent mitral valve surgery (98% repair) for DMR. All patients had preoperative, predischarge, and follow-up (mean, 5.0 ± 3.6 years) echocardiograms. Speckle tracking was performed in 119 of 520 patients (22.9%) to determine LV strain, right ventricular free-wall strain, and left atrial longitudinal strain. Multivariate logistic and Cox regression models were used in this subgroup to evaluate associations with early postoperative LV dysfunction and medium-term overall survival, respectively. Results: Median preoperative LVEF of the entire cohort was 65%. Based on predischarge echocardiogram, 449 patients (86.3%) maintained postoperative LVEF of 50% or greater. Seventy-one patients (13.7%) had a predischarge LVEF of less than 50%, 49 (9.4%) had a predischarge LVEF of 40% to 49%, and 22 (4.2% overall) had a predischarge LVEF of less than 40%. Abnormal preoperative LV, right ventricular, and left atrial strain measurements were significantly associated with the development of postoperative LV dysfunction, but preoperative hemodynamic and non-strain echo parameters did not vary enough in absolute values to be clinically useful as predictors of postoperative LV dysfunction. Conclusions: Preoperative strain measurements in DMR patients were significantly associated with superior capabilities of detecting underlying LV dysfunction despite preserved preoperative LVEF. Strain analysis may serve as another marker for optimal timing of surgical intervention in DMR patients.