Abstract 17439: Radial Artery Intima-Media Thickness is Predictive of Major Cardiovascular Events in Patients with Suspected Coronary Artery Disease during a Three Years Follow-Up Period

Abstract

Background: Intima-media thickness in carotid artery (cIMT) is a well-known surrogate marker of atherosclerosis. Recently, using very high-resolution ultrasound, we showed that the radial artery could be imaged with high precision and its structure seemed to be related to various cardiovascular risk factors. Since atherosclerosis is a systemic vascular disease, we hypothesized that radial artery intima-media thickness (rIMT) is predictive of major adverse cardiovascular events (MACE) in patients with suspected coronary artery disease (CAD).

Methods: A total of 416 patients (mean age 62±9 years, 183 male) with suspected CAD undergoing myocardial perfusion scintigraphy (MPS) were recruited. 2D images of carotid and radial artery were acquired bilaterally using 8 MHz and 55 MHz ultrasound (resolution 20 µm) respectively. Average values of IMT measured in left and right artery were used. A number of plasma biomarkers were also analyzed. All patients were followed up after three years with regard to MACE (death, MI, stroke and cardiovascular revascularization).

Results: rIMT correlates with cIMT (r=0.33, p<0.001), age (r=0.31, p<0.001), gender (r=0.39, p<0.001), systolic blood pressure (r=0.25, p<0.001), hyperlipidemia (r=0.15, p=0.002) and MPS-verified ischemia (r=0.17, p<0.001). During mean follow-up of 3.03 years, 77 MACE occurred. Patients with MACE versus no MACE showed significantly greater rIMT (0.348±0.06 mm compared with 0.316±0.07 mm, p<0.001). In Kaplan-Meier survival analysis, rIMTbelow median value (0.318 mm) were significantly associated with three-year event-free survival rate (p<0.001). Patients with rIMT above median value had nearly three-fold greater risk for occurrence of MACE (HR 2.8, 95% CI 1.6-4.8). In multivariate Cox analysis, including age, gender, hypertension, hyperlipidemia, type-II-diabetes, ischemia verified by MPS, cIMT>median and rIMT>median; rIMT>median remains an independent predictor of MACE (p=0.041), alongside with cIMT>median (p=0.027) and ischemia verified by MPS (p<0.001).

Conclusion: Radial artery IMT may be a new vascular surrogate marker of atherosclerosis and seems to confer prognostic information in patients with suspected coronary artery disease.