Beyond Chamber-Level Function: Residual Global Work Index and Reverse Remodeling After Reperfused STEMI

Background: Left ventricular remodeling after myocardial infarction is heterogeneous, and conventional baseline measures of systolic function only partly anticipate its course. Left ventricular ejection fraction (LVEF) and myocardial work reflect different aspects of systolic performance. We examined whether deviation of global work index (GWI) from the value expected for LVEF is associated with reverse remodeling after reperfused ST-elevation myocardial infarction (STEMI). Methods: In 101 prospectively enrolled patients with single-vessel STEMI, echocardiography was performed 12–24 h after reperfusion and at 12 ± 2 months. Residual GWI (GWIr) was calculated as observed GWI minus regression-predicted GWI for the corresponding LVEF. The primary outcome was follow-up 3D end-systolic volume (3D-ESV), adjusted for baseline. Results: Of 60 patients with paired imaging, 58 had baseline GWI; 18 showed reverse remodeling (≥15% 3D-ESV reduction). Each 1-SD higher GWIr was associated with 3.74 mL lower follow-up 3D-ESV (95% CI −6.70 to −0.77; p = 0.015) and higher odds of reverse remodeling (odds ratio 2.38, 95% CI 1.28–5.01; p = 0.005). For the continuous outcome, absolute GWI had a comparable point estimate with a wider confidence interval. Conclusions: Higher GWIr, indicating myocardial work higher than expected for LVEF, was associated with lower follow-up 3D-ESV and higher odds of reverse remodeling after adjustment for baseline 3D-ESV. These exploratory findings require external validation.