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Modern implantable medical devices have evolved beyond serving as physical surrogates, to also playing an active role in restoring bodily functions. The progress of implantable medical devices is the culmination of advances in various scientific fields such as material science, microelectronics and biomaterials. The use of polymers in biomedical applications is highly attractive, especially in soft tissue applications as polymers have the potential to elicit appropriate host tissue response. However, homopolymers often do not encompass all the desired characteristics such as mechanical properties, degradability, biocompatibility or bio-functionality. The concepts of polymer blending or polymer composites were introduced to overcome the inadequacies when using a single polymer in cardiovascular applications. Through polymer blending, polymer scaffolds made up of two or more polymers can yield scaffold stiffness closer to the human myocardium and improved hydrophilicity for better cell interaction and improved biodegradability. Polymer composites, which utilizes to reinforce the base polymer, have demonstrated improved the compliance of the vascular graft similar to human native vessels. This review presents an overview of fabrication techniques and novel applications of polymer blends and polymer composites in cardiovascular implants, ranging from coronary stents to tissue engineered constructs. [ABSTRACT FROM AUTHOR]

Advances in material science and innovative medical technologies have allowed the development of less invasive interventional procedures for deploying implant devices, including scaffolds for cardiac tissue engineering. Biodegradable materials (e.g., resorbable polymers) are employed in devices that are only needed for a transient period. In the case of coronary stents, the device is only required for 6–8 months before positive remodelling takes place. Hence, biodegradable polymeric stents have been considered to promote this positive remodelling and eliminate the issue of permanent caging of the vessel. In tissue engineering, the role of the scaffold is to support favourable cell-scaffold interaction to stimulate formation of functional tissue. The ideal outcome is for the cells to produce their own extracellular matrix over time and eventually replace the implanted scaffold or tissue engineered construct. Synthetic biodegradable polymers are the favoured candidates as scaffolds, because their degradation rates can be manipulated over a broad time scale, and they may be functionalised easily. This review presents an overview of coronary heart disease, the limitations of current interventions and how biomaterials can be used to potentially circumvent these shortcomings in bioresorbable stents, vascular grafts and cardiac patches. The material specifications, type of polymers used, current progress and future challenges for each application will be discussed in this manuscript. [ABSTRACT FROM AUTHOR]