Assessment of Systemic Adenosine Effect Using Color Doppler Ultrasound of the Splenic Artery-Feasibility and Potential Clinical Utility for Coronary Interventions.

Adenosine induces coronary vasodilation and simultaneously reduces splanchnic perfusion. This effect can be absent in adenosine non-responders. Imaging of splanchnic arteries under adenosine assessing this effect has not been performed in humans previously. In 26 patients, splenic artery color Doppler was performed during an infusion of adenosine. Peak velocity in the splenic artery was measured before the infusion and at 2 min. Results were compared qualitatively with perfusion imaging in magnetic resonance. A total of 24 patients showed a drop of splenic artery peak velocity from 62.3 ± 18.1 to 40.4 ± 15.7 cm/s (p <0.001), which corresponded to perfusion restriction in magnetic resonance. Two patients with constant splenic artery velocity did not show perfusion restriction. We showed feasibility of assessing changes in splenic artery velocity under adenosine for the first time in humans. Further studies are needed to investigate whether this novel application is a robust tool to rule out inadequate adenosine effect during measurement of fractional flow reserve in coronary catheterization.