- Researchers create a bioreactor that enables the heart tissue to shrink in sync with electrical stimulation.
- They used very small pieces of heart tissue with preserved function and structure to build this device.
- It allows scientists to finetune contraction parameters through computer programs to mimic real heart conditions.
As one of the vital organs, the human heart was long recognized as the seat of life that propels blood through two different circuits. It pumps blood with a rhythm determined by a set of pacemaking cells in the sinus node (located in the wall of the right atrium).
Although scientific understanding of the heart dates back to the ancient world, the first successful human heart transplant surgery didn’t take place until 1967. By this time, heart disease had surpassed infectious disease as the leading cause of death in the US.
Today, more than 3,500 heart transplant surgeries are performed every year worldwide, more than 50% of them occur in the US. Then we have a concept of the artificial heart to permanently replace the actual heart in case heart transplantation isn’t possible.
Scientists have been working on this concept for more than 5 decades and they have managed to achieve a little success. Numerous continuous-flow ventricular assist devices have been developed for this process, some of them are undergoing clinical trials for FDA approval.
Studying Hearts In Lab
Studying hearts in the laboratory is a challenging task because they are very sensitive to external environments. This fist-sized powerhouse beats nearly 100,000 times per day, pumping 6 quarts of blood every minute.
Hearts in unhealthy people work less efficiently than normal, and this happens due to various possible causes. In this case, blood moves through the body and heart at a much slower rate, and pressure within the heart raises.
In the laboratory, heart tissues undergo remodeling, which makes it even harder to analyze heart physiology and create new medicines for diseases associated with the heart.
To address this issue, researchers at Imperial College London developed a new system to investigate heart tissue in the physiological environment. They presented their work at the 63rd Biophysical Society Annual Meeting in Maryland.
A Custom Bioreactor
A human heart works by pumping the blood to the body and while doing so it expands and contracts up to 100 times per minute. This is not something we have achieved in vitro heart models.
Source: Biophysical Society
Now researchers have successfully recapitulated the sequence of events as found in the human body, using very small pieces of heart tissue with preserved function and structure. To do this, they created a customized bioreactor that enables the tissue to shrink in sync with electrical stimulation.
Courtesy of researchers
To verify whether this system accurately mimics an actual heart, they simulated normal surroundings, by adding noradrenaline and changing the workload on the tissue. As expected, the resulting changes in force were similar to those observed in real hearts.
This system could be extremely useful in medical fields, as doctors can promptly finetune contraction parameters through computer programs to mimic normal or special disease conditions. For instance, they can recreate rigid conditions of high blood pressure to better understand what happens to the tissue at those levels.