Measuring adenosine in coronary sinus blood has been confounded by rapid metabolism of this nucleoside during the transit of blood through a long catheter. In this study, we tested the combination of a 145-cm dual-lumen catheter, a double-compartment syringe, and a “stop-solution,” designed to prevent adenosine metabolism, for use in sampling blood from a central site for determination of plasma adenosine concentration
To simulate conditions of increased adenosine plasma levels at the sampling site, six different concentrations of adenosine (0.4 to 20 mol/L) in stop-solution were delivered to the central sampling site at the moment of blood withdrawal. The recovery of adenosine in the collected samples was 74.1%±8.7% of that delivered. To assess the ability to detect increased endogenous adenosine release, atrial pacing to induce myocardial ischemia was performed and plasma coronary sinus adenosine measured in nine patients (five with and four without severe coronary artery disease)
In all patients in whom atrial pacing resulted in myocardial ischemia, plasma adenosine in the coronary sinus increased immediately after termination of pacing and returned to baseline 5 minutes later. In none of the patients without ischemia did adenosine level increase. In a second clinical application of the system, coronary sinus adenosine was measured in six men undergoing coronary artery bypass surgery. On reperfusion (aortic crossclamp release), coronary sinus adenosine level increased eightfold from baseline, reflecting myocardial ischemia. These levels remained elevated (P < 0.05) up to 12 minutes after aortic crossclamp release with a smaller secondary rise after termination of cardiopulmonary bypass.
We have developed a new dual-lumen catheter, double-compartment syringe method for sampling human blood from the coronary sinus that allows the detection of elevated plasma adenosine.
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