Experimental myocardial necrosis course during alginate hydrogel implantation, saturated with extract of cryopreserved piglet heart fragments (histological examination).

Background. New methods for therapy and prevention of complications in acute myocardial necrosis are aimed to limit the necrosis areas, and to prevent the heart rupture and heart failure development. With this aim, during the heart muscle remodeling one applies the alginate implants, which not only prevent the cardiac aneurysm, but may be a depot of biologically active substances and/or cell suspensions as well, ensuring thereby the diffusion of the latter into the affected area. Objective. To analyze the histological material of the hearts after cryonecrosis and the introduction of alginate implants into the damage zone saturated with a cryopreserved extract of heart fragments of the piglets in dynamics. Methods. The experimental studies were carried out in 78 outbred male rats. Myocardial necrosis was simulated by affecting the left ventricular wall by means of cryoinstrument with 3 mm applicator diameter at working surface temperature of -195°C for 30 s. Either alginate implant or the implant, saturated with the piglet heart extract (PHE) was injected into cryonecrosis area. The extract was derived from cryopreserved fragments of newborn piglet hearts. Results. It was established the fact, that in the animals of all experimental groups after cryoexposure to the heart, the myocardial remodeling proceeded by the classical pathway from an aseptic inflammation to the formation of connective tissue scar. The use of alginate implants, saturated with cryopreserved heart fragments of piglets accelerated the reparative processes in the heart and reduced the degree of remodeling of the left ventricular myocardium. Conclusion. Analysis of histological preparations of the heart showed that in the animals with myocardial cryonecrosis after introducing an alginate implant, and especially the PHE-saturated alginate implant, a newly formed scar tissue with mature collagen fibers and blood vessels developed in the affected area in earlier terms (to days 7 and 14, respectively), as compared to myocardial cryonecrosis, that suggested the trophic restoration in affected area of the myocardium.