The aim – to assess flow-dependent vasodilation in acute phase of STEMI and determine the association of impaired reactive hyperemy with no-/slow-reflow syndrome development and clinical complications of STEMI. Decreased flow-mediated brachial artery dilation (FMD) was associated with death and cardiovascular events in different categories of patients but was not thoroughly studied in recent acute MI.
Material and methods. 151 patients with ST elevation MI were investigated. All patients were admitted during first 12 hours after symptoms onset and treated according to current guidelines. Endothelium-dependent FMD was measured using high-resolution ultrasound at admission (13.8±1.5 hours after MI onset) and at day 7.
Results. Patients with recent ST elevation MI had initially reduced brachial artery FMD with further improvement of endothelial function to day 7 (6.41±0.53 % at day 1 vs 8.25±0.49 % at day 7, Р=0.014). The results of FMD test at the day of admission were not associated with any of the major risk factors, MI characteristics or initial laboratory markers, except glucose level (r=– 0.29, Р=0.004).
Conclusions. Patients with preserved endothelial function at day 1 significantly more often had complete recovery of coronary microcirculation (Myocardial Blush Grade 3) after primary PTCA (83.7 % of patients with FMD ≥ 5 % vs 66.7 % of patients with FMD < 5 %, Р=0.047). Impaired reactive hyperemy (FMD < 5 %) was associated with no- /slow-reflow development and complicated index hospitalisation (death and acute heart failure development). The worst hospital outcomes were observed in patients with FMD ≤ 0 %.