Reduced adenosine receptor expression in ACS patients with no-reflow phenomenon undergoing primary PCI.

Introduction: Acute coronary syndrome (ACS) patients undergoing primary percutaneous coronary intervention (PPCI) often experience the no-reflow phenomenon (NRP), characterized by reduced myocardial perfusion despite an open coronary artery. Adenosine, a potent vasodilator, is used to aid reperfusion. To elucidate underlying molecular mechanism of this phenomenon, we investigated expression of ADORA2A and ADORA2B genes, encoding adenosine receptors, in ACS patients with NRP and non-NRP.

Methods: We conducted a case-control study of 102 ACS patients undergoing PPCI, including 51 patients with NRP (TIMI flow grade 0 or 1) and 51 non-NRP patients with normal flow (TIMI flow grade 2 or 3). Gene expression was measured using Real-Time PCR.

Results: Analysis showed significantly reduced expression of both ADORA2A and ADORA2B genes in NRP patients compared to non-NRP (p < 0.01). Furthermore, we observed a direct and moderate correlation between the two genes in NRP patients (r = 0.45, p = 0.001), whereas the correlation was stronger and more direct in non-NRP (r = 0.8, p = 0.0001).

Conclusion: Reduced adenosine receptor expression may contribute to the NRP in ACS patients undergoing PPCI. These findings highlighted the importance of understanding molecular mechanisms underlying this phenomenon to develop targeted therapies aimed at improving cardiac reperfusion.