An organosynthetic dynamic heart model with enhanced biomimicry guided by cardiac diffusion tensor imaging

Abstract

The complex motion of the beating heart is accomplished by the spatial arrangement of contracting cardiomyocytes with varying orientation across the transmural layers, which is difficult to imitate in organic or synthetic models. High-fidelity testing of intracardiac devices requires anthropomorphic, dynamic cardiac models that represent this complex motion while maintaining the intricate anatomical structures inside the heart. In this work, we introduce a biorobotic hybrid heart that preserves organic intracardiac structures and mimics cardiac motion by replicating the cardiac myofiber architecture of the left ventricle. The heart model is composed of organic endocardial tissue from a preserved explanted heart with intact intracardiac structures and an active synthetic myocardium that drives the motion of the heart. Inspired by the helical ventricular myocardial band theory, we used diffusion tensor magnetic resonance imaging and tractography of an unraveled organic myocardial band to guide the design of individual soft robotic actuators in a synthetic myocardial band. The active soft tissue mimic was adhered to the organic endocardial tissue in a helical fashion using a custom-designed adhesive to form a flexible, conformable, and watertight organosynthetic interface. The resulting biorobotic hybrid heart simulates the contractile motion of the native heart, compared with in vivo and in silico heart models. In summary, we demonstrate a unique approach fabricating a biomimetic heart model with faithful representation of cardiac motion and endocardial tissue anatomy. These innovations represent important advances toward the unmet need for a high-fidelity in vitro cardiac simulator for preclinical testing of intracardiac devices.

Soft, tough, and fast polyacrylate dielectric elastomer for non-magnetic motor

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“…Another monumental achievement in heart simulation presented the development of an organosynthetic, biohybrid heart model that uses custom molded silicone and advanced tissue adhesion capabilities to fabricate a synthetic ventricular myocardium on an explanted porcine heart ( 99 ). Researchers implanted pneumatic actuators as the contractile elements in the synthetic myocardium to drive heart function.…”

News & Views

“…The complex motion of the beating heart is an essential characteristic of a high-fidelity in vitro model for the preclinical testing of intracardiac devices, but this characteristic has been particularly difficult to imitate in vitro . To contribute to this area of unmet preclinical testing need, Park et al 1 followed a unique approach: a biohybrid strategy that combined organic and synthetic components. To reproduce the complex arrangement of cardiac fibres, the team took inspiration from the helical ventricular myocardial band theory, which postulates that the ventricle can be unravelled into a singular muscular band that is spirally arranged in the 3-D space.…”