Fixing failing hearts
September 29, 2017
September 29 is World Heart Day, a time to focus on cardiac health
In Dr. Stefan Jovinge’s lab, a petri dish of cells is doing something interesting.
Every few seconds, a one-two drum beat rolls across its surface, visible only through the lens of a microscope.
If the sound was audible, it would be familiar one—the lub-dub thumping of a human heart.
These cells are more than just a neat scientific trick. They could help change the way we treat one of the world’s biggest health threats.
A global problem
Cardiovascular diseases are the number one cause of death globally, and claim the lives of more than 17 million people each year, according to the World Health Organization.
It’s a broad umbrella under which a multitude of conditions fall, such as coronary heart disease, cardiac arrest, congenital heart disease and heart failure.
But it’s this last one—heart failure—that has scientists and physicians alike particularly concerned. It results when the heart can no longer pump blood efficiently throughout the body and can be caused by a number of factors, such coronary disease, the aftermath of a heart attack or diseases that place a strain on the system such as diabetes.
Their concern mirrors a worrying trend. In January, the American Heart Association reported that the number of adults with heart failure in the U.S. increased markedly from 5.7 million in 2009–2012 to 6.5 million in 2011–2014. That figure is expected to rise 46 percent by 2030, an increase of more than 8 million people.
“Heart failure is the new epidemic,” said Jovinge, a seasoned scientist and critical care cardiologist who directs the DeVos Cardiovascular Research Program at Van Andel Research Institute and Spectrum Heath. “We need new ways to help these patients that go beyond current treatment strategies and that focus on repairing damaged muscle.”
Rewriting the code
Healing the heart isn’t like healing another organ. When the heart experiences an injury, like a heart attack, trauma or lack of blood flow from a blocked artery, the damage is permanent.
That’s because the muscle cells that comprise it, for the most part, lose their ability to replicate as we age. New cells aren’t able to replace old, damaged or dead ones.
“When it comes to treatment, we often have to manage the symptoms of the injury and delay progression of disease, rather than treating the injury itself,” Jovinge said. “For people whose hearts have been seriously damaged, there is little we can do in the way of repair other than a heart transplant.”
That’s where the cells in the petri dish come in. Called induced pluripotent stem cells, or iPS cells for short, they are the result of complex bioengineering that transforms them from normal adult blood cells into two types of heart muscle cells—cardiomyocytes and pacemaker cells.
Check out the videos above to see ventricular heart muscle cells and pacemaker cells in action. Pacemaker cells beat faster and control the heart’s ability to beat.
Jovinge’s team hopes to one day use them as a biological bandage of sorts, applying them to damaged heart tissue to coax the growth of new, healthy cells, or as a way to deliver new medications that prompt cell growth.
They’re testing their approach rigorously in the laboratory, along with other methods such as analyzing billions of genetic data points to identify risk factors and potential drug treatments for a variety of heart conditions, and sorting out exactly why cardiomyocytes stop replicating. Eventually, they plan to weave their findings into human clinical trials.
“Regenerative medicine is the next frontier,” Jovinge said. “We’re very hopeful that this work will one day lead to a new, improved treatments that help people live longer, healthier lives.”
Dr. Stefan Jovinge leads the DeVos Cardiovascular Research Program, a joint effort between Spectrum Health and Van Andel Research Institute. For more information on their work, please visit devoscvresearch.org.