# Pharmacologic Profile of A2A Adenosine Receptors: Identifying Patients with Intermittent Claudication and Associated Myocardial Ischemia

## TL;DR

This study explores how adenosine A2A receptor profiles in blood cells can help identify patients with leg artery disease who also have heart artery blockages.

## Contribution

The study introduces a novel pharmacologic profile of A2A adenosine receptors to detect obstructive coronary artery disease in peripheral artery disease patients.

## Key findings

- A2AR expression and EC50 were lower in patients with positive FFR, indicating obstructive CAD.
- The A2AR profile may serve as a biomarker for identifying CAD in LE-PAD patients.
- Patients with LE-PAD and positive FFR showed distinct A2AR characteristics compared to those with negative FFR.

## Abstract

Low-extremity peripheral artery disease (LE-PAD) is often associated with coronary artery disease (CAD). Development of biomarkers is needed to identify those among LE-PAD patients who have associated CAD. The pharmacologic profile of adenosine A2A receptors (A2AR; expression, cyclic adenosine monophosphate [cAMP] production, half maximal effective concentration [EC50]) evaluated on peripheral blood mononuclear cells is useful because these parameters are modified during myocardial ischemia. A total of 127 patients were included; 75 with CAD had a positive flow-fraction-reserve (FFR) but no intermittent claudication. Among those with LE-PAD, 27 had a positive FFR, and 25 had a negative FFR. The A2AR expression and EC50 were lower in patients with a positive FFR vs a negative FFR. Obstructive CAD might be detected by measuring the adenosine A2AR profile.