Abstract 16975: Endothelial Microparticles as a Diagnostic Tool for the Detection of Subclinical Myocardial Ischemia
Background: Endothelial microparticles (EMP) provide information about prognosis and future cardiovascular risk. So far, no study evaluated whether myocardial ischemia induced by stress testing influences the EMP level and whether these changes could substantially add to the diagnostic accuracy of the stress test. Aim of this study was to evaluate the association of the EMP release after dobutamine-stress echocardiography (DSE) with the prevalence of coronary artery disease (CAD) and compare its diagnostic accuracy for the detection of CAD with established biomarkers such as NT-proBNP and troponin I (TnI).
Methods and results: In this prospective, single-center interventional study, all patients underwent DSE before left heart catheterization. Blood was drawn before, 4h, and 24h after DSE. Plasma CD144-positive EMP levels were measured by fluorescence activated cell sorting (FACS) analysis. We enrolled 70 patients (age: 66.0±10.2 yrs.; 66% male; SYNTAX score: 9.6±10.1) of whom 12 patients did not suffer from CAD. Baseline levels of NT-proBNP [272.0 (104.0/703.0) vs. 64.5 (50.8/104.8) pg/ml; P=0.030] - but not of TnI [<0.02 (<0.02/<0.02) vs. <0.02 (<0.02/<0.02) ng/ml; P=0.77] and CD144-EMP [356.9 (97.2/829.1) vs. 354.6 (108.4/752.1); P=0.75] - differed significantly between patients with CAD compared to patients without CAD. At 4 hours after DSE, CD144-EMP (P=0.026), NT-proBNP (P=0.004), and TnI levels (P=0.025) were significantly higher in CAD patients compared with non-CAD patients. In ROC-curve analysis, the CD144-EMP level (AUC 0.71, 95% CI: 0.54-0.88) was superior to the TnI level (AUC 0.67, 95% CI: 0.51-0.83) but inferior to the NT-proBNP level (AUC 0.78, 95% CI: 0.65-0.90).
Conclusions: The level of CD144-positive EMP was significantly higher after dobutamine stress echocardiography in patients suffering from CAD, but was not superior to NT-proBNP and TnI in the detection of CAD (study ID: DRKS00000737).
- Endothelial function
- Ischemic heart disease
- Stress echocardiography
- Coronary artery disease
- © 2012 by American Heart Association, Inc.