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Melt electrowriting (MEW) is an electric-field-assisted additive biofabrication technique that has brought significant advancements to bioinspired scaffold design for soft tissue engineering and beyond. Owing to its targeted microfiber placement, MEW has become a powerful platform technology for the fabrication of in vitro disease models up to functional biohybrid constructs that are investigated in vivo to reach clinical translation soon. This work provides a concise overview of this rapidly evolving field by highlighting the key contributions of MEW to cardiovascular tissue engineering. Specifically, we i) pinpoint the methods to introduce microvascular networks in thick 3D constructs benefitting from (sacrificial) MEW microfibers, ii) report MEW-based concepts for small-diameter vascular grafts and stents, iii) showcase how contracting cardiac tissues can profit from the tunable structure–property relationship of MEW scaffolds, and iv) address how complete regenerative heart valves can be built on complex fiber scaffold architectures that recapitulate J-shaped tensile properties and tissue heterogeneity. Lastly, we touch on novel biomaterial advancements and discuss the technological challenges of MEW to unlock the full potential of this transformative technology.

Melt electrowriting (MEW) is an electric‐field‐assisted fiber‐forming biofabrication strategy for the additive manufacturing (AM) of precisely defined 3D microarchitectures. MEW is based on pressure‐driven extrusion of a polymer melt pool, currently mainly implemented at laboratory scale with specialized machine technology and limited to only few materials. This precludes the accessibility of MEW to a broader user group and can become the bottleneck of MEW's technological advancement. In contrast to conventional MEW, a filament‐based approach (F‐MEW) is introduced that exploits the technological ecosystem of fused filament fabrication (FFF), a globally used transformative AM technique. In this work, a polymer filament serves as feedstock material and is melted just on demand. By upgrading existing FFF systems, MEW of polymer microfibers is enabled, as validated with polycaprolactone (PCL) and demonstrated with direct writing of thermosensitive polydioxanone (PDO). Finally, FFF and F‐MEW are hybridized in a dual‐mode AM process. This enables multiscale constructs featuring both FFF struts and one order of magnitude smaller F‐MEW microfibers. This work opens the accessibility of F‐MEW to the large FFF user group, potentially benefitting from the plethora of filaments available for FFF, while, at the same time, expanding the FFF fabrication window.