Changes in Global Left Ventricular Myocardial Work Indices and Stunning Detection 3 Months After ST-Segment Elevation Myocardial Infarction

Abstract

Global left ventricular (LV) myocardial work (MW) indices (GLVMWI) are derived from speckle tracking echocardiographic strain data in combination with non-invasive blood pressure measurements. Changes in global work index (GWI), global constructive work (GCW), global wasted work (GWW) and global work efficiency (GWE) after ST-segment elevation myocardial infarction (STEMI) have not been explored. The aim of present study was to assess the evolution of GLVMWI in STEMI patients from baseline (index infarct) to 3 months' follow-up. Three-hundred and fifty patients (265 men; mean age 61 § 10 years) with STEMI treated with primary percutaneous coronary intervention (PCI) and guideline-based medical therapy were retrospectively evaluated. Clinical variables, conventional echocardiographic measures and GLVMWI were recorded at baseline within 48 hours post-primary PCI and 3 months' follow-up. LV ejection fraction (from 54 § 10% to 57 § 10%, p < 0.001), GWI (from 1449 § 451 mm Hg% to 1953 § 492 mm Hg%, p < 0.001), GCW (from 1624 § 519 mm Hg% to 2228 § 563 mm Hg%, p < 0.001) and GWE (from 93% (interquartile range (IQR) 86%-95%) to 95% (IQR 91%-96%), p < 0.001) improved significantly at 3 months' follow-up with no significant difference in GWW (from 101 mm Hg% (IQR 63-155 mm Hg%) to 96 mm Hg% (IQR 64-155 mm Hg%); p = 0.535). On multivariable linear regression analysis, lower values of troponin T at baseline, increase in systolic blood pressure and improvement in LV global longitudinal strain were independently associated with higher GWI and GCW at 3 months' follow-up. In conclusion, the evolution of GWI, GCW and GWE in STEMI patients may reflect myocardial stunning, whereas the stability in GWW may reflect permanent myocardial damage and the development of non-viable scar tissue.

Impact of Myocardial Scars on Left Ventricular Deformation in Type 2 Diabetes Mellitus After Myocardial Infarction by Contrast-Enhanced Cardiac Magnetic Resonance

“…Previous studies have shown that there is a correlation between the extent of MI and LV deformation in acute MI patients 9,30 . However, after acute MI, with the absorption of myocardial edema and in ammation, or infarction core ber gliosis, the delayed enhancement area of LGE imaging changes.…”

Usefulness of echocardiographic myocardial work in evaluating the microvascular perfusion in STEMI patients after revascularization

“…Echocardiographic myocardial work parameters have also been proven [ 28 ] to be good markers for segmental myocardial viability both in core zone and remote zone following myocardial infarct assessed by contrast-enhanced cardiac magnetic resonance in STEMI patients after PCI. One study assessed the evolution of LVMW in 350 STEMI patients from baseline to 3 months’ follow-up [ 29 ]. It is suggested that the evolution of GWI, GCW and GWE in STEMI patients may reflect myocardial stunning, whereas the stability in GWW may reflect permanent myocardial damage.…”

Impact of myocardial scars on left ventricular deformation in type 2 diabetes mellitus after myocardial infarction by contrast-enhanced cardiac magnetic resonance

“…Previous studies have shown a correlation between the extent of MI and LV deformation in acute MI patients [ 9 , 28 ] [. However, after acute MI, with the absorption of myocardial edema and inflammation, or infarction core fiber gliosis, the delayed enhancement area of LGE imaging changes.…”