Aims: Left ventricular (LV) end-systolic diameter and LV ejection fraction (LVEF) are correlated with postoperative LVEF and prognosis in patients with organic mitral regurgitation (MR). However, in some patients, the LVEF does not return to normal 6 months postoperatively, despite normal preoperative diameters. Thus, our study aimed to evaluate whether preoperative LV strain values assessed by echocardiography at rest and during exercise were predictors of postoperative LVEF at 6-month follow-up in patients undergoing surgery for severe organic MR.
Methods and results: In total, 88 patients with severe organic MR (mean age 62.6 ± 1.4 years) were prospectively recruited. All patients underwent an echocardiogram at rest and submaximal exercise (110 ± 10 bpm) prior to surgery and then at rest 6 months after surgery. Exclusion criteria were significant coronary artery disease, other organic valvular diseases, uncontrolled arrhythmia, and haemodynamic instability. Among the 88 patients, 77 had complete data sets with rest and exercise echocardiograms and underwent isolated mitral valve surgery (repaired, n= 72). Global longitudinal strain (GLS) at rest (R= -0.42, P= 0.011) and during exercise (R= -0.36, P= 0.034) correlated with postoperative LVEF. When normalized for LV end-systolic diameter, GLS during exercise was more closely correlated with postoperative LVEF and was its best predictor based on a multivariate linear regression model. At a cut-off of -5.7%/cm, sensitivity was 0.83, specificity 0.70, negative predictive value 0.64, and positive predictive value 0.86 for predicting a 6-month postoperative LVEF of <50%.
Conclusion: In patients undergoing surgery for severe organic MR, GLS normalized for LV end-systolic diameter at submaximal exercise may be used as a predictor of postoperative LVEF.