Left Ventricular Global Longitudinal Strain as a Marker of Left Ventricular Dysfunction after Mitral Valve Surgery in Organic Mitral Regurgitation

Abstract

Introduction Due to lack of reliable echocardiographic parameters to predict recovery after the surgery, the optimal timing of mitral valve surgery in asymptomatic patients with mitral regurgitation (MR) remains controversial. Therefore this study sought to evaluate left ventricular (LV) global longitudinal strain (GLS), assessed with 2 dimension speckle-tracking echocardiographic analysis (2D- STE) as a predictor of LV dysfunction after mitral valve repair (MVR). Method We conducted a meta-analysis and searched MEDLINE, EMBASE, and Cochrane. Selected studies reported GLS and ejection fraction (EF) amongst asymptomatic patients with moderate to severe organic MR and preoperative preserve LVEF. In all studies echocardiography was performed at baseline and long-term follow-up (>6 months) after MVR. The two primary outcomes were the pooled standardized mean difference (SMD) of EF and GLS between patients with LV dysfunction at follow up which was defined as LVEF Result Four studies met the inclusion criteria. A total of 799 patients (65.9% men, mean age 61.3) with moderate to severe organic MR who underwent successful MVR were included. LV dysfunction at follow up was present in 57 (16.2%) patients. The mean preoperative LVEF and LVGLS were 63.8% (SD 6.4) and −20.7 (SD 3.2), respectively. Many relevant outcomes were inconsistently recorded across studies and thus only a select few were eligible for further analysis. Notably, patients with postoperative LVEF ≥ 50% had a more negative GLS at baseline (i.e. closer to normal) when compared to the group with post-operative LV dysfunction (GLS pooled SMD = 2.94; 95% CI: 1.87-4.02; I-squared 17%, tau-squared heterogeneity p = 0.15). Furthermore, using baseline GLS as a predictor of post-op LV dysfunction was associated with a sensitivity of 79% (95% CI: 0.75-0.83) and a specificity of 75% (95% CI: 46-96%). Conclusion In asymptomatic patients with moderate to severe organic MR and preoperative normal LVEF who underwent MVR, LVGLS demonstrated to be a predictor of postoperative LV dysfunction.