Long-term, regular remote ischemic preconditioning improves endothelial function in patients with coronary heart...

Area of Science:

• Cardiovascular Research
• Vascular Biology
• Regenerative Medicine

Background:

• Coronary artery disease (CHD) is a leading cause of mortality.
• Endothelial dysfunction is a key factor in CHD pathogenesis.
• Remote ischemic preconditioning (RIPre) shows potential for cardioprotection.

Purpose of the Study:

• To evaluate the long-term effects of regular RIPre on human arterial endothelial function.
• To investigate the impact of RIPre on endothelial progenitor cells and underlying molecular mechanisms in patients with CHD.

Main Methods:

• Forty patients undergoing coronary artery bypass graft (CABG) surgery were randomized into RIPre and CHD groups (n=20 each).
• A control group (n=20) of mastectomy patients was included.
• RIPre involved cycles of 5-minute arterial occlusion followed by 5-minute reperfusion, repeated 4 times, 3 times daily for 20 days.
• Endothelial function (flow-mediated dilation - FMD), CD34(+) monocyte count, eNOS expression, and STAT-3/Akt phosphorylation were assessed in arterial samples.

Main Results:

• Long-term RIPre significantly improved FMD in the RIPre group compared to the CHD group (8.5±2.4% vs 4.9±4.2%, P<0.05).
• Troponin levels post-CABG surgery were significantly reduced in the RIPre group.
• RIPre activated STAT-3 signaling and increased CD34(+) endothelial progenitor cell counts.

Conclusions:

• Regular, long-term RIPre enhances endothelial function in patients with CHD.
• STAT-3 activation appears to be a key mechanism mediating RIPre's benefits.
• RIPre may promote vascular repair through an increase in endothelial progenitor cells.