Thermo-sensitive copolymers for the treatment of arterial aneurysms

Aneurysms (blood filled bulges in the wall of a blood vessel) are among the most common of all lethal cardiovascular conditions. While open surgery and minimally invasive techniques can be used to treat the condition, treatment efficacy, follow up treatment and subsequent management of the healing process is often hindered by the occurrence of endoleaks; leakage into the aneurysm sack after endovascular repair. Furthermore, accessing specific treatment sites located in regions of complex tortuosity remains extremely challenging. The premise of this research is to determine the feasibility of deploying smart, thermo-responsive hydrogels as 'filler' materials which can be applied to the affected site using a novel, minimally invasive, catheter delivery technique; with a particular focus on the mechanical and thermo-responsive properties of said hydrogel materials. Different concentrations of poly(poly(ethylene oxide) and poly(propylene oxide) tri-block copolymers, with varying solution-solvent ratios, were studied using calorimetric and rheological techniques. Results show that specific solute-solvent concentrations have potential for use when coupled with a temperature controlled catheter delivery system. However, optimal temperature control remains challenging.