Endothelial function impairment in STEMI patients with out-of-hospital cardiac arrest under therapeutic hypothermia treatment

Abstract

Background: Therapeutic hypothermia (HT) in out-of-hospital cardiac arrest STEMI patients aims to improve their neurological prognosis, but it has been associated with slow coronary flow and cardiac thrombotic events. We sought to serially assess endothelial function during the first 48h after admission in out-of-hospital cardiac arrest STEMI patients, under therapeutic hypothermia (HT).

Methods: From January 2015 to August 2015, eighteen consecutive out-of-hospital cardiac arrest STEMI patients eligible for primary PCI received HT at admission and were included in the study (HT group). During the same time period, eight consecutive patients with large anterior STEMI who received primary PCI but not HT were included as control group. Serial endothelial function by measuring flow-mediated dilatation (FMD) in the brachial artery, biomarkers of endothelial function and oxidative stress were assessed during the first 48h after admission in both groups.

Results: HT group showed worse FMD as compared to the control group (p<0.001). Glutathione peroxidase-3 (GPx-3) values were higher in control as compared to HT group (p=0.019), without any interaction between time of observation and HT (p=0.864). A significant interaction between time and HT was found in the levels of sVCAM-1, which reached an earlier peak in control than in HT group (p=0.019). ET-1 values generally increase overtime (p=0.005), but without any main effect of HT (p=0.175).

Conclusions: HT is associated with endothelial dysfunction in out-of-hospital cardiac arrest STEMI patients during the first 48h after admission. This vascular dysfunction may be related to increased oxidative stress due to deficiency of GPx-3 in HT patients.

Keywords: Cardiac arrest; Endothelial function; Hypothermia.