Abstract 17934: Bevacizumab for Plaque Stabilization: Evaluation of its Effect on Vasa Vasorum, Lipid Pool, and Atheroma Volume by Multimodality Imaging Techniques in an Atherosclerotic Rabbit Model
Background: Adventitial vasa vasorum may play an important role in plaque progression and rupture by allowing inflammatory cells and red blood cells to penetrate into the plaque through the channels.
Objective: This study was designed to evaluate the effect of bevacizumab (anti-VEGF antibody) on inhibition of vasa vasorum and plaque stabilization in a rabbit atherosclerotic model.
Methods: Atherosclerotic plaque was induced in New Zealand white rabbits by balloon injury to the carotid artery followed by a high-fat diet for 12 weeks and a relatively low-fat diet for 8 weeks. Animals with atherosclerotic plaques were randomized into control group or bevacizumab group after baseline contrast-enhanced carotid ultrasound (CECU), intravascular ultrasound (IVUS) and optical coherence tomography (OCT) were performed at week 12. Bevacizumab (7.5mg/kg) was administered intravenously at week 12 and 16. At week 20, CECU, IVUS and OCT were repeated. Enhancement intensity (EI) indicating vasa vasorum density was measured by CECU. Total atheroma volume (TAV) was measured by IVUS and lipid arc by OCT. The number of vasa vasorum was counted after staining with monoclonal antibody CD31.
Results: At week 20, EI was significantly lower in the bevacizumab group compared with control group (11.2±1.5dB vs. 19.1±3.5dB, p=0.005, Figure 1A). TAV and lipid arc were also significantly smaller in the bevacizumab group (99.2±10.8 mm3 vs. 120±13.8 mm3, p=0.03, Figure 1B; 238±29.2° vs. 325.4±24.8°, p=0.001, Figure 1C).
Conclusions: Bevacizumab inhibits development of vasa vasorum, plaque progression, and lipid accumulation in atherosclerotic plaques in this rabbit model. Inhibition of VEGF may be one of the strategies for plaque stabilization. Figure 1:
- Interventional cardiology
- Intravascular ultrasound/Doppler
- Cardiovascular imaging
- © 2012 by American Heart Association, Inc.