The development of conducting polymeric nanocomposites patches for cardiac tissue engineering has opened new possibilities for restoring the health of infarcted heart tissues. Herein, we report the fabrication of biocompatible and relatively cost-effective poly(vinyl alcohol)/alginate-based hydrogels patches modified with different conducting nanofillers such as silver nanoparticles, polyaniline nanofibers, copper oxide nanoleaves, and graphene oxide nanosheets. The impact of the different nanofiller materials on the molecular structure, charge transport mechanism and mechanical characteristics of the designed nanocomposites patches was investigated. In addition, some significant parameters of the nanocomposites were characterized such as swelling ability, antioxidant activity as well as hemocompatibility. Infrared spectroscopy results demonstrated the occurrence of different interactions between the included nanofillers and the polymer matrix depending on the type of the nanofiller. Moreover, conductivity measurements revealed that only the polyaniline nanofibers-modified nanocomposites hydrogels showed the highest conductivity compared to other counterparts. Mechanical characterization, antioxidant activity, swelling and hemocompatibility proved the suitability of the developed polyaniline nanofibers-modified nanocomposites hydrogels as potential candidates for successful application in cardiac tissue engineering.