Prognostic utility of global longitudinal strain (GLS) in patients with severe primary mitral regurgitation undergoing mitral valve surgery: a systematic review and meta-analysis

Abstract

Abstract Background Mitral valve (MV) surgery is recommended for the treatment of chronic severe mitral regurgitation (MR). However, the optimal timing of surgery in patients with asymptomatic severe primary MR remains elusive. Global longitudinal strain (GLS) may provide additional prognostic value in predicting postoperative outcomes in patients with chronic severe primary mitral regurgitation (MR) undergoing MV surgery. Purpose We aimed to determine the prognostic value of GLS in predicting postoperative mortality and LV dysfunction among patients with chronic severe primary MR. Methods Systematic search of Pubmed, Cochrane library, Clinicaltrials.gov, and Herdin.ph from inception to July 2019, using the terms “mitral insufficiency”, “mitral regurgitation”, “mitral valve surgery”, and “global longitudinal strain” was done without language restriction. We included and extracted data from cohort studies of patients with chronic severe primary MR who underwent MV surgery and which GLS, mortality and ejection fraction. We used the Newcastle Ottawa Scale to assess the quality of included studies. Review Manager 5.3 was used to perform analysis. Forest plots with summary hazard ratios (HR) and odds ratios (OR) with 95% confidence intervals (CI), I2 test for heterogeneity, and funnel plots were reported. Results Our search yielded 12 cohort studies with 2,843 patients; 7 prospective and 5 retrospective studies were included in the qualitative synthesis with 11 good quality studies. Cut-off GLS values ranged from −21.7% to −18.1%. In terms of postoperative all-cause mortality, the summary HR for worse versus better preoperative GLS is 1.22 (95% CI 1.04–1.44, p value <0.ehab724.16031, I2 95%). In terms of postoperative LV dysfunction, the summary OR is 1.74 (95% CI 1.14–2.66, p value 0.01, I2 94%) with significant heterogeneity. Conclusion Left ventricular GLS has prognostic value in terms of predicting postoperative mortality and LV dysfunction. However, significant heterogeneity exists between studies. Larger studies with well-defined inclusion criteria need to be performed and standardized GLS cut-offs need to be determined. Funding Acknowledgement Type of funding sources: None. GLS in Predicting All-Cause MortalityGLS in Predicting Post-op Dysfunction