A cardiac patch from aligned microvessel and cardiomyocyte patches

Area of Science:

• Cardiovascular Research
• Regenerative Medicine
• Biomaterials Science

Background:

• Cardiac tissue engineering seeks to create functional myocardial replacements.
• Current limitations include lack of preformed microvascularization, restricting patch thickness and force output.
• This hinders effective treatment for infarcted myocardium.

Purpose of the Study:

• To assess the efficacy of a bilayer cardiac patch in a rat infarct model.
• The patch combines human induced pluripotent stem cell-derived cardiomyocytes with an engineered microvessel layer.
• To evaluate its engraftment, perfusion, and functional improvements.

Main Methods:

• Constructed a bilayer patch with cardiomyocyte and microvessel layers (endothelial cells and pericytes).
• Cultured the patch in vitro and implanted it onto the epicardial surface of nude rat infarct models.
• Assessed patch functionality, survival, maturation, and vascular integration using perfusion labels and histology.

Main Results:

• Bilayer patches showed increased twitch force, improved cardiomyocyte survival and maturation in vitro.
• Engineered microvessels exhibited larger lumens compared to single-layer controls.
• Implanted patches demonstrated microvessel sprouting, inosculation with host vasculature, and perfusion.

Conclusions:

• The engineered microvessel layer significantly enhances in vitro cardiac patch functionality.
• Bilayer cardiac patches achieve successful engraftment and rapid vascular integration on injured myocardium.
• This bilayer approach enables future development of thicker, more powerful cardiac tissues.