Potential of predicting mildly reduced and reduced left ventricular ejection fraction in patients in the post-infarction period

Abstract

Aim. To analyze ischemic and reperfusion injury characteristics, as well as myocardial performance, to identify predictors of reduced left ventricular (LV) ejection fraction (EF) <50% 24 weeks after ST-segment elevation myocardial infarction (STEMI) in patients who underwent revascularization.Material and methods. The study included were 65 patients (age 58 (52; 60) years), who were examined on days 7-10 and after 24 weeks. Based on cardiac magnetic resonance imaging (MRI), parameters of ischemic and reperfusion injury were determined. Speckle tracking echocardiography was used to evaluate the myocardial function.Results. All 65 patients completed the study. Based on echocardiography, patients were divided into following groups: 1 — 45 people with LVEF ≥50%, 2 — 20 patients with LVEF <50%. In patients with LVEF ≥50% 24 weeks after STEMI, there was a decrease in the ischemia injury mass by 32,3% (p=0,001) due to regression of the scar mass by 28% (p=0,008) and the peri-infarct heterogeneous zone by 33,3% (p=0,020). In group 2, the indicators did not change. At the repeat visit, there was a decrease in the number of people with microvascular obstruction in the group of LVEF ≥50% from 44 to 16% (p<0,001), while in LVEF <50% — from 65 to 40% (p=0,045). According to echocardiography, global wasted work in group 1 decreased from 77 (50,5; 105,5) to 59 (43; 92) mm Hg% (p=0,042), while in group 2, it increased from 99,5 (59; 181) to 104,5 (58,5; 156,5) mm Hg% (p=0,765). Global work efficiency and global work index prevailed in patients with LVEF ≥50% at two visits (p<0,05). The following predictors of decreased LVEF were determined 24 weeks after STEMI: ischemia injury mass, scar tissue, microvascular obstruction, global contrast index according to MRI; global work efficiency and global work index on echo cardiography.Conclusion. Contrast-enhanced cardiac MRI and speckle tracking echocardiography are complementary methods that allow quantitative morphofunctional assessment of post-infarction cardiosclerosis and predict the development of mildly reduced and reduced LVEF in the medium term.