Adenosine Stress Test

Q: What is the mechanism behind using Adenosine for chemical stress test?

Answer: Adenosine causes vasodilation in the small and medium-sized arterioles (less than 100 µm in diameter). When adenosine is administered, it causes a coronary steal phenomenon, where the vessels in healthy tissue dilate as much as the ischemic tissue, and more blood is shunted away from the ischemic tissue that needs it most. This is the principle behind adenosine stress testing.

Adenosine is quickly broken down by adenosine deaminase, which is present in red cells and the vessel wall.

#cardiolgy

References:

1. Müller-Suur R, Eriksson SV, Strandberg LE, Mesko L. Comparison of adenosine and exercise stress test for quantitative perfusion imaging in patients on beta-blocker therapy. Cardiology. 2001;95(2):112-8. doi: 10.1159/000047356. PMID: 11423717.

2. Alzahrani T, Khiyani N, Zeltser R. Adenosine SPECT Thallium Imaging. 2022 Sep 12. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan–. PMID: 30725755.