Abstract 13919: Enhanced Rho-kinase Activity in Circulating Neutrophils in Patients with Vasospastic Angina—Possible Usefulness for Diagnosis and Disease Activity Assessment-
Background: We have previously demonstrated that activated Rho-kinase pathway plays a central role in the molecular mechanism of coronary vasospasm in animal models and patients with vasospastic angina (VSA). However, it remains to be examined whether Rho-kinase activity is systemically enhanced in VSA patients and if so, whether a non-invasive diagnostic method could be developed for better practice of VSA.
Methods: We examined 50 consecutive patients with chest pain (M/F 31/19, 59±13 [SD] years) who underwent acetylcholine provocation test for coronary spasm. They were divided into the 2 groups, depending on the response to the test; VSA (n=30) and control group (n=20). Venous blood samples were collected to measure Rho-kinase activity in circulating neutrophils, determined by the extent of phosphorylation of myosin binding subunit (MBS), a substrate of Rho-kinase.
Results: Although high sensitivity C-reactive protein (hsCRP) levels and the accumulated number of coronary risk factors were comparable between the 2 groups, the Rho-kinase activity was significantly higher in the VSA group than in the control group (phosphorylated MBS/total MBS ratio, 1.30±0.37 vs. 0.95±0.20, P<0.001). With ROC curve analysis, phosphorylated ratio 1.18 was identified as the best cut-off level to predict the diagnosis of VSA (Figure A). In the VSA group, no correlation was noted between Rho-kinase activity and hsCRP, smoking habit or accumulated number of coronary risk factors. After the 3-month medical treatment, Rho-kinase activity in the VSA group was significantly decreased to 1.10±0.35 (P<0.05), and %change in the Rho-kinase activity correlated with the degree of improvement in symptoms (Figure B).
Conclusions: These results indicate that Rho-kinase activity in circulating neutrophils is enhanced in VSA patients and may be useful for the diagnosis and disease activity assessment of the vasospastic disorder.
- © 2010 by American Heart Association, Inc.