Lab-Grown Human Heart: Bioartificial Left Ventricle Devised to Better Understand Cardiovascular Diseases, Potential Treatments

A new lab-grown small-scale model of a human left heart ventricle could offer researchers a new way of studying a wide range of heart ailments and conditions, not to mention, testing out potential treatments.

As specified in a EurekAlert! report the University of Toronto Engineering researchers have developed the said heart model in the laboratory.

The bioartificial construct is built with living heart cells beating strongly enough to pump fluid inside a bioreactor.

The left ventricle in the human heart is the one that pumps freshly oxygenated into the aorta, and from there, into the remaining parts of the body.

Organ on a Chip

According to Sargol Okhovatian, with the said model, they can gauge ejection volume, the amount of fluid that's getting pushed out every time the ventricle contracts, and the pressure of that particular fluid. Both of these, he added, were almost impossible to get with previous models.

Okhavatian and Mohammad Hossein Mohammadi are co-lead authors of the new paper published in the Advanced Biology journal, where the model they designed is described. Their multidisciplinary team was led by the paper's senior author, Professor Milica Radisic.

All three researchers are part of the Centre for Research and Applications in Fluidic Technologies.

The unique facilities the researchers have at CRAFT enable them to develop sophisticated organ-on-a-chip models like this newly-devised artificial heart, Radisic explained.

She also said that with their models, they could study not just cell function but tissue and organ function, minus the need for invasive surgery or animal experimentation.

Scaffolds Made from Biocompatible Polymers

The unique facilities can also be used to screen large libraries of drug candidate molecules either for positive or negative impacts.

A lot of these challenges that face tissue engineers are linked to geometry. While it is easy to grow human cells in two dimensions, for instance, a similar Science Magazine report said that in a flat petri dish, the outcomes don't look as similar to real tissue or organs as they would occur in the human body.

Radisic's team used small scaffolds made from biocompatible polymers to move into three dimensions. These said scaffolds, frequently patterned with gloves or mesh-like structures, are seeded with heart muscle cells. They are also left to grow in a liquid medium.

Addressing Vasculature Problem

Describing their model, Radisic said their model has three layers, although a real heart would have 11. She added, that they can add more layers, but that's making it heart for oxygen to diffuse through, "so the cells in the middle layers" begin to die.

Actual hearts have vasculature or blood vessels to address the problem; thus, there is a need to find a way to replicate that.

According to Okhovatian, in addition to the vasculature problem, future work will focus on increasing the cells' density to increase the pressure and volume. She also wants to find a way to shrink or ultimately remove the scaffold, which an actual heart would not have.

Even though the proof-of-concept model demonstrates substantial progress, there is still a long way to go before totally functional artificial organs are possible.

Related information about artificial hearts is shown on France 24 English's YouTube video below:

Check out more news and information on Heart Health and Technology in Science Times.