Novel thermosensitive hydrogel injection inhibits post-infarct ventricle remodelling

Myocardial infarction (MI) remains the commonest cause of cardiac-related death throughout the world. Adverse cardiac remodelling and progressive heart failure after MI are associated with excessive and continuous damage of the extracellular matrix (ECM). In this study, we hypothesized that implantation of hydrogel into infarcted myocardium could replace the damaged ECM, thicken the infarcted wall, and inhibit cardiac remodelling.

MI was induced in rabbits by coronary artery ligation; 4 days later, 200 microL Dex-PCL-HEMA/PNIPAAm gel solution was injected into the infarcted myocardium. Injection of phosphate-buffered saline served as control. Thirty days after treatment, histological analysis indicated that injection of the biomaterial prevented scar expansion and wall thinning compared with controls. Echocardiography studies showed that injection of hydrogel increased left ventricular ejection fraction and attenuated left ventricular systolic and diastolic dilatation. Haemodynamic analysis demonstrated improved cardiac function following implantation of the hydrogel.

These results suggest that injection of thermosensitive Dex-PCL-HEMA/PNIPAAm hydrogel is an effective strategy that prevents adverse cardiac remodelling and dysfunction in MI rabbits.