Values of Radial Artery Provocation Tests at Different Doses of Ergonovine in the Diagnosis of Coronary Artery Spasm

The intracoronary drug provocation test has been the gold standard for diagnosis of coronary artery spasm (CAS); however, it has been identified with severe complications. In this study, we investigated the sensitivity, specificity, and safety of radial artery provocation test at different doses of ergonovine in the diagnosis of CAS. This study enrolled 57 patients, which were then divided into CAS group (n = 24) and control group (n = 33) after intracoronary ergonovine provocation test. All patients underwent radial artery provocation test at different doses of ergonovine. The predictive values of radial artery provocation test for the diagnosis of CAS were analyzed using receiver operator characteristic curve. In the radial artery provocation test at different doses of ergonovine, radial artery stenosis degree was all found to be significantly higher in the CAS group than in the control group (all P < 0.001). In the control group, significant differences were noted in the radial artery stenosis degree between different doses of ergonovine (all P < 0.05). In the CAS group, the radial artery stenosis degree was significantly higher in 160 μg and 100 μg of ergonovine than in 60 μg of ergonovine (all P < 0.001). The radial artery provocation test at 60 μg and 100 μg of ergonovine did not cause CAS, chest pain, and ECG ischemic changes. In the radial artery provocation test at 160 μg of ergonovine, some patients had CAS, chest pain, and ECG ischemic changes. The specificity and sensitivity of radial artery provocation test were 90.91% and 50.00% at 60 μg of ergonovine, 96.97% and 66.67% at 100 μg of ergonovine, and 90.91% and 95.83% at 160 μg of ergonovine for the diagnosis of CAS. As per our findings, we can conclude that the basic tension of radial artery increases in the CAS group. With the increase of ergonovine doses, its sensitivity and specificity improve, but its safety decreases. We will explore the most optimal dose of ergonovine in future studies.