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A remarkable challenge in myocardial tissue engineering is the development of biomimetic constructs that can potentially improve myocardial repair and regeneration. Polyurethane (PU) scaffolds are extensively utilized in the cardiovascular system. We have synthesized a new biodegradable poly­(ester-ether urethane urea) (PEEUU) using a new and simple method. To enhance mechanical and physicochemical properties, the PEEUU was blended with polycaprolactone (PCL). We then fabricated a series of new PU–PCL scaffolds. The scaffolds were then characterized using SEM, porosity measurement, attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), DSC, water contact angle measurement, swelling measurement, in vitro degradation rate, and mechanical tests. Expression of the cardiac-specific proteins on the scaffolds was investigated using immunofluorescence staining and quantitative real-time PCR. The elasticity of blends increased with an increase of PEEUU. In the blend scaffolds, the size and interconnectivity of pores were in an appropriate range (142–170 μm) as reported in the literature. These blend scaffolds revealed high cell metabolic activity for cardiomyoblasts and also enabled cells to proliferate and express cardiac marker proteins at higher rates. Histological examination of subcutaneously transplanted scaffolds after two months revealed degradation in the blend scaffolds. It is demonstrated that functionality of cells is sensitive to the composition of biomaterials used, and the effective cell–biomaterial interactions are critical in order to create a functional tissue engineered product that allows seeded cells to develop their normal activity. The PEEUU–PCL blends could potentially provide a versatile platform to fabricate functional scaffolds with an effective cell–biomaterial interaction for cardiac tissue regeneration.

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Conductive nanofibers have been considered as one of the most interesting and promising candidate scaffolds for cardiac patch applications with capability to improve cell–cell communication. Here, we successfully fabricated electroconductive nanofibrous patches by simultaneous electrospray of multiwalled carbon nanotubes (MWCNTs) on polyurethane nanofibers. A series of CNT/PU nanocomposites with different weight ratios (2:10, 3:10, and 6:10wt%) were obtained. Scanning electron microscopy, conductivity analysis, water contact angle measurements, and tensile tests were used to characterize the scaffolds. FESEM showed that CNTs were adhered on PU nanofibers and created an interconnected web‐like structures. The SEM images also revealed that the diameters of nanofibers were decreased by increasing CNTs. The electrical conductivity, tensile strength, Young's modulus, and hydrophilicity of CNT/PU nanocomposites also enhanced after adding CNTs. The scaffolds revealed suitable cytocompatibility for H9c2 cells and human umbilical vein endothelial cells (HUVECs). This study indicated that simultaneous electrospinning and electrospray can be used to fabricate conductive CNT/PUnanofibers, resulting in better cytocompatibility and improved interactions between the scaffold and cardiomyoblasts.

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Despite recent advances in medicine and surgery, many people still suffer from cardiovascular diseases, which affect their life span and morbidity. Regenerative medicine and tissue engineering are novel approaches based on restoring or replacing injured tissues and organs with scaffolds, cells and growth factors. Scaffolds are acquired from two major sources, synthetic materials and naturally derived scaffolds. Biological scaffolds derived from native tissues and cell-derived matrix offer many advantages. They are more biocompatible with a higher affinity to cells, which facilitate tissue reconstruction. Interestingly, xenogeneic recipients generally tolerate their components. Therefore, heart valve tissue engineering is increasingly benefiting from naturally derived scaffolds. In this review, we investigated the different protocols and methods that have been used for heart valve decellularization.

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