Differential recovery of myocardial systolic global strain after STEMI

Abstract

Background: STEMI-related acute myocardial injury is characterised by hibernation and stunning. However, little is known about differential recovery of myocardial contractility following percutaneous coronary revascularisation (PCI) in STEMI. The aim was to examine the pattern of myocardial contractile recovery following STEMI, using paired echocardiographic strain analysis. Methods: Thirty consecutive patients who underwent PCI for STEMI were included. Clinical and demographics data were collected prospectively. All patients had paired echo measurements at early (day 2-7 days post-STEMI) and late (after 2 months) global longitudinal strain (GLS). GLS was measured from apical 4-, 2-chamber and long-axis views, yielding LV multilayered (endo-, mid-, epi-cardial) datasets. Results: Patients were 56±10 years of age, risk factors were diabetes (8%), smoker (69%); hypertension (39%) and dyslipidaemia (35%). There was a reduction in GLS in all 3 layers at baseline compared to normal (22±10, published values), with some recovery at 2 months (Table 1). Although percentage changes for recovery of GLS were similar across the 3 myocardial layers (p=0.994), a significant improvement was seen only in endocardial GLS (p<0.05).Table 1% change in GLS between index and follow-up.BaselineFollow-up% changeEndo-GLS (%)-15.4±5.0-18.1±4.2-19.2±34.3Mid-GLS (%)-13.6±4.4-15.8±3.8-20.4±35.5Epi-GLS (%)-12.1±3.9-13.9±3.4-19.7±36.8 Open table in a new tab Conclusions: There is an increase in multilayer GLS over 2 months following STEMI. However, significant improvement is observed only in endocardial GLS. Thus, after STEMI, recovery of endocardial GLS may appear to occur first. Longer term follow up is required to confirm these findings.