New Device Reduces Scarring In Damaged Blood Vessels

New Device Reduces Scarring In Damaged Blood Vessels
(Image source)
When blood vessels are damaged through surgery, it can trigger an endless cycle of scarring and repair. Scar tissue will always form inside the blood vessel and, in many cases, eventually block blood flow. Then surgeons have to go back in, eliminate the obstruction, or put in a new graft or stent to restore blood flow. In the case of a prosthetic vascular graft used for bypass surgery, it will scar again and ultimately fail. Now, researchers have developed a new material that, when applied to damaged blood vessels, can prevent scarring and stop the cycle before it begins. The research is published in the the American Journal of Physiology: Heart and Circulatory Physiology.
 
The soft, porous, and thin elastic material contains an acid form of vitamin A, called a retinoid, which is produced by the body to help cells develop and stay healthy. Synthetic retinoids have been formulated and traditionally used to treat acne and some types of cancer. Unfortunately, the oral dose needed to positively affect vessel healing and prevent scarring could never be administered to humans as it is toxic in very high doses. However, the researchers solved this by incorporating the retinoid into a biodegradable membrane that can be handled and implanted by a surgeon.
 
The researchers started with an inherently antioxidant, citrate-based polymer previously developed in the laboratory. Then they added the all-trans retinoic acid (atRA), a vitamin A derivative. The membrane was evaluated in an animal model. When wrapped around the outside of a damaged blood vessel, it created a favorable environment for the healing process, and the researchers noted a 50-60 percent reduction of scar formation compared to vessels without the membrane.
 
Damaged cells typically produce aggressive signals that cause their neighboring cells to become inflamed. The material "keeps the cells quiet", so dangerous messages do not spread to the rest of the vessel. The membrane achieves local exposure to atRA, protecting the blood vessel and regulating how it responds to injury.
 
Whether or not you employ a stent or attach a prosthetic graft to a blood vessel, you injure it. The vessel's response to the injury can get out of control. With this fairly simple method, the inflammatory response can be controlled and adequate blood flow through the vessel maintained.