Dynamic Changes in Myocardial Function Early and Long-Term After Mitral Valve Surgery Detected by Speckle-Tracking Echocardiography
Background: It is known that mitral valve surgery produces an early reduction in hemodynamic overload after the procedure. However, the reduction in left ventricular (LV) ejection fraction (EF) may persist over the long term. Speckle-tracking echocardiography (STE) provides more sensitive indices of cardiac performance in MR. Myocardial work (MW) evaluates LV performance by considering the effect of LV afterload. The aim of this study was to describe the acute and late postoperative changes in cardiac function and hemodynamics using STE and MW indices in patients with primary MR and to find echocardiographic predictors of postoperative symptom improvement. Methods: Consecutive patients with severe MR and preserved LV EF undergoing mitral valve repair or replacement were prospectively enrolled. Exclusion criteria were atrial fibrillation, previous cardiac surgery, and concomitant aortic or coronary surgery. Patients underwent clinical, biohumoral and echocardiographic evaluation before surgery and within one week after surgery during the hospitalization period. Then, 32 of them underwent a new echocardiographic exam, completed by MW, at long-term follow-up. Results: Overall, 42 patients were enrolled (mean age 65 ± 12 years, 50% male, mean LV EF 59 ± 4%). After intervention, 48% of patients showed a reduction in LV EF (n = 20), while most patients showed reductions in STE and MW parameters across all chambers. Particularly, the global work index (GWI) was reduced in 79% of patients (n = 33). After a mean long-term follow-up of 26 ± 5 months, all STE parameters significantly improved in >70% of patients (n = 22), while LV EF maintained its initial reduction. A baseline value of LV GLS > −17.7% identified patients with persistence of symptoms at long-term follow-up (AUC 0.68, p = 0.02). Conclusions: After an initial decline, LV function detected by GLS improved over the long term after mitral valve surgery, paralleling a reduction in symptoms. STE indices might provide additional value for the long-term follow-up of patients undergoing mitral valve repair/replacement.