The role of E-wave velocity in predicting early left ventricular dysfunction and significant decline in left ventricular ejection fraction after mitral valve repair for severe chronic primary mitral regurgitation.

Abstract

Preoperative left ventricular (LV) ejection fraction (LVEF) and LV end-systolic dimension (LVESD) are established predictors of LV dysfunction (LVD) after mitral valve repair (MVr) for mitral regurgitation (MR). Although elevated estimated right ventricular systolic pressure (eRVSP) indicating pulmonary hypertension is the best proposed additional predictor, we hypothesized that transthoracic echocardiography (TTE) parameters more directly reflecting left atrial pressure (LAP) would more accurately predict LVD than eRVSP. Furthermore, predictors of a significant decline in LVEF remain unknown. We retrospectively studied 622 patients, aged 20-87 years, who underwent MVr for severe chronic primary MR. As previously reported predictors of postoperative LVD, we collected seven preoperative TTE parameters, including LVESD, LVEF, eRVSP, LV end-diastolic dimension, left atrial volume index (LAVI), early transmitral annular (e') velocity, and atrial fibrillation. Furthermore, as LAP-related TTE parameters, we collected left atrial dimension, E-wave velocity, and E/e' ratio, in addition to eRVSP and LAVI. Using multivariate logistic regression and receiver operating characteristic curve analyses, we explored predictors of early postoperative LVD, defined as LVEF < 50% measured on postoperative day 7. We further explored predictors of a significant decline in LVEF, defined as an absolute decline in LVEF of > 12 percentage points, the third quintile of the data. Incidences of postoperative LVD and a significant LVEF decline were 12.9% and 23.2%, respectively. In addition to LVESD and LVEF, E-wave velocity, but not eRVSP, remained a significant predictor of postoperative LVD. E-wave velocity, LVESD, and LVEF had additive effects in risk prediction. Furthermore, E-wave velocity was the strongest predictor of a significant LVEF decline. E-wave velocities > 121.5 cm/s and > 101.5 cm/s were associated with increased risks of postoperative LVD (odds ratio [OR], 2.896; 95% confidence interval [95%CI], 1.792-4.681; p < 0.001) and a significant LVEF decline (OR, 6.345; 95%CI, 3.707-10.86; p < 0.001), respectively. After adjustment for multiple TTE parameters, E-wave velocity, but not eRVSP, remained significant predictors of postoperative LVD and a significant LVEF decline after MVr. These results were reproducible in 461 patients who underwent follow-up TTE at 1 year, suggesting an important role of E-wave velocity in risk prediction.