From Fiber Architecture to Functional Attachment: A Clinically Relevant, Mechanically Tunable Cardiac Patch

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Cardiovascular Engineering

Background:

• Engineered cardiac patches show promise for myocardial infarction treatment as biological ventricular assist devices (BioVADs).
• Optimal patch design and attachment are critical for mechanical support of damaged hearts but remain underexplored.
• Current approaches lack personalized mechanical properties and robust integration strategies.

Purpose of the Study:

• To develop and validate a personalized, multi-zonal engineered cardiac patch platform for myocardial infarction treatment.
• To investigate the interplay between scaffold microarchitecture and mechanical properties for optimal cardiac support.
• To evaluate the efficacy of the designed BioVAD in a preclinical myocardial infarction model.

Main Methods:

• Computational modeling to design a multi-zonal microarchitecture (regenerative, force transmission, attachment zones).
• Melt electrowriting (MEW) fabrication using a custom G-code generator.
• Digital image correlation and biaxial testing to characterize scaffold mechanics and zonal strain differences.
• Epicardial suture retention testing and dynamic BioVAD cultivation with cardiomyocytes.
• In vivo evaluation in a porcine myocardial infarction model.

Main Results:

• The scaffold exhibited distinct zonal mechanics with up to a 2.6-fold strain difference, mimicking native myocardium up to 10% strain.
• A reinforced outline improved suture retention by 2.16-fold, enabling shape-morphing for attachment.
• Dynamic cultivation significantly enhanced cardiomyocyte alignment (p = 0.01).
• In vivo, the BioVAD achieved complete epicardial attachment and vascular ingrowth within 7 days.

Conclusions:

• Melt electrowriting is a versatile platform for creating personalized cardiac scaffolds with tailored mechanical properties.
• The developed multi-zonal BioVAD platform effectively supports tissue integration and cardiac function post-myocardial infarction.
• This approach offers a promising strategy for developing next-generation cardiac regenerative therapies.