Influence of unrecovered bloodflow phenomenon in patients with acute myocardial infarction with ST segment elevation after percutaneous coronary intervention on the dynamics of some echocardiography indicators during long-term follow-up

The aim — to determine the effect of unrecovered bloodflow phenomenon (UBF) after percutaneous coronary intervention (PCI) on the dynamics of changes in the end-diastolic index (EDI), end systolic index (ESI) and left ventricular (LV) ejection fraction (EF) in patients with acute myocardial infarction with ST segment elevation (STEMI).Materials and methods. The study involved 105 patients aged 36 to 85 years (on average 60.4 ± 2.0 years, who were hospitalized in Kharkiv City Clinical Hospital N 8 between January 2014 and September 2017, diagnosed with STEMI, and underwent PCI on average in 7.6 ± 1.2 hours after the onset of the first signs of the disease. The UBF was determined using the MBG (Myocardial Blush Grade) index as the lack of optimal myocardial perfusion in case of the MBG index ≤ 2 points. The main group consisted of 12 (16.7 %) patients with UBF, control group — of 60 (83.3 %) patients whose angiographic data corresponded to the criteria of successful PCI. During the follow-up, 72 patients enrolled in the study underwent echocardiography three times, on average 1.1 ± 0.6, 9.3 ± 1.2 and 8.3 ± 0.6 months after the invasive interference. Criteria for unfavorable LV remodeling were an increase in LV EDI by more than 20 % in 8.3 ± 0.6 months compared to the initial value and an increase in LV ESI to more than 35 ml/m2. The criterion of adverse changes in EF in 8.3 ± 0.6 months after AMI was its value ≤ 40 %.Results and discussion. The initial echocardiographic characteristics of both groups of patients did not differ significantly. Patients of the main group showed significantly worse LV remodeling results on echocardiography compared with the control group: an increase in EDI by more than 20 % of baseline (OR 10.6, 95 % CI 2.63 — 4.2.65, p < 0.05), an increase in ESI ≥ 35 ml/m2 (OR 4.46, 95 % CI 1.21 — 16.46, p < 0.05), a more dynamic increase in ESI (OR 4.1, 95 % CI 1.05 — 15.60; p < 0.05), absence of significant LVEF dynamics in 8.3 ± 0.6 months (OR 14.00, 95 % CI 3.06 — 63.99, p < 0.05), while in the control group, patients prevailed with a positive dynamics of increase in LVEF > 5 % (OR 0.05, 95 % CI 0.06 — 0.41, p < 0.05). There were no statistically significant differences in the number of patients with EF ≤ 40 % between the study groups (p > 0.05).Conclusions. The development of UBF in the form of myocardial perfusion abnormalities after PCI in patients with STEMI is associated with the development of unfavorable LV remodeling in 8.3 ± 0.6 months of observation, namely, with an increase in EDI and ESE of the LV, and no positive LVEF dynamics.