Self-expanding endovascular stent in experimental atherosclerosis. Work in progress

Area of Science:

• Biomedical Engineering
• Vascular Biology
• Medical Device Research

Background:

• Endovascular prostheses, or stents, are crucial in treating vascular diseases.
• Understanding stent interactions with atherosclerotic vessels is vital for improving patient outcomes.
• Previous studies in canines showed intimalization of stents in healthy aortas.

Purpose of the Study:

• To evaluate the physiologic and histologic responses to self-expanding endovascular prostheses in rabbits.
• To compare stent performance in healthy aortas versus aortas with induced atherosclerosis.
• To determine if stents contribute to atherogenesis or offer protective effects in diseased vessels.

Main Methods:

• Rabbits were fed a high-cholesterol diet and subjected to intravascular trauma to induce atherosclerosis.
• Self-expanding stents were implanted in the aortas of these rabbits.
• Control stents were implanted in healthy rabbit aortas for comparison.

Main Results:

• Stents in healthy aortas induced intimalization, consistent with prior canine studies.
• In rabbits with high-cholesterol diets but no trauma, stents did not initiate atherogenesis.
• Stents implanted in existing atheromatous plaque led to plaque compression and fibrotic crust formation over time.

Conclusions:

• Self-expanding stents do not cause atherogenesis when placed in a high-cholesterol environment without prior trauma.
• Stents demonstrate a protective effect by compressing atherosclerotic plaque and forming a fibrotic crust.
• These findings suggest endovascular prostheses can mitigate progressive lumen encroachment by atherosclerotic tissue.