Determinants of post-operative left ventricular dysfunction in degenerative mitral regurgitation

Abstract Funding Acknowledgements Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): The Saudi Arabian Cultural Bureau. Background Chronic degenerative mitral regurgitation leads to volume overload causing left ventricular (LV) enlargement and eventually LV impairment. Current guidelines determining thresholds for intervention are based on LV diameters and ejection fraction. There is sparse data examining the value of LV volumes and newer markers of LV performance on outcomes of surgery in mitral valve prolapse. Purpose Identify the best markers of LV impairment after mitral valve surgery. Methods Prospective, observational study of patients with mitral valve prolapse undergoing mitral valve surgery. Pre-operative LV diameters, volumes, ejection fraction (LVEF), global longitudinal strain (GLS) and myocardial work measured. Post-operative LV impairment defined as LVEF < 50% at 1 year post-surgery. Results Eighty-seven patients included. 13% developed post-operative LV impairment. Patients with post-operative LV dysfunction showed significantly larger indexed LV end-systolic diameters (LVESD), volumes (LVESV), lower LVEF and more abnormal GLS than patients without post-operative LV dysfunction. In multivariate analysis, indexed LVESV (Odds ratio 1.11 (95% CI 1.01 – 1.23), p = 0.039) and GLS (odds ratio 1.46 (95% CI 1 – 2.14), p = 0.054) were the only independent predictors of post-operative LV dysfunction. The optimal cut-off of 36.3 ml/m2 for indexed LVESV had a sensitivity of 82% and specificity of 78% for detection of post-operative LV impairment. Conclusion Post-operative LV impairment is common. Indexed LV volumes (36.3ml/m2) provided the best marker of post-operative LV impairment.