According to the Centers for Disease Control and Prevention, heart failure affects almost 7 million US adults and accounts for 14% of yearly deaths. There is currently no cure, although medications slow its progression. In other advanced cases that are not eligible for transplant, the last recourse is pump replacement by something called an artificial heart, also known as the left ventricular assist device, to help the heart pump blood.
Skeletal muscle has a profound ability to regenerate after injury. If you are playing soccer and you tear a muscle, you need rest, which will heal. When a heart muscle is injured, it never grows back. There is nothing to reverse heart muscle loss.
A research team, led in part by a physician-scientist, is collaborating with co-intervention programs in various institutes, such as Scottsdale Healthcare in the US. They investigate whether certain groups of patients who have had artificial hearts can regenerate heart muscle, which opens avenues to a new therapy or a future cure for heart failure.
The international collaboration investigates whether heart muscles can regenerate. The project began with tissue from artificial heart patients provided by colleagues at the University of Utah Health and School of Medicine, led by Stavros Drakos, MD, PhD, a pioneer in left ventricular assist device-mediated recovery.
To determine whether these samples contained newly created cells, the scientists employed their own novel technique of carbon dating human heart tissue.
They found that patients with artificial hearts regenerated muscle cells at more than six times the rate of healthy hearts.
New stem cell combination could help to repair damaged hearts
Hesham Sadek, MD, PhD, director of the Sarver Heart Center and chief of the Division of Cardiology at the U of A College of Medicine — Tucson’s Department of Medicine, said, “This is the strongest evidence we have, so far, that human heart muscle cells can actually regenerate, which really is exciting because it solidifies the notion that the human heart has an intrinsic capacity to regenerate.”
“It also strongly supports the hypothesis that the inability of the heart muscle to ‘rest’ is a major driver of the heart’s lost ability to regenerate shortly after birth. Targeting the molecular pathways involved in cell division may be possible to enhance the heart’s ability to regenerate.”
He pondered whether the artificial heart gives cardiac muscles the equivalent of bed rest in a person recuperating from a soccer injury. These results and those of other research teams showed that a small percentage of patients could have their devices removed after experiencing a reversal of symptoms.
“The pump just pushed blood into the aorta, bypassing the heart,” he said. “The heart is resting essentially.”
Sadek’s previous research had already suggested rest might have a very positive effect on heart muscle cells, but it was a matter of designing an experiment to find out if these patients with artificial hearts were truly regenerating muscle.
“There has never been hard evidence of heart muscle regeneration at the cellular level in humans,” he said. “This study provides the direct evidence.”
Next, Sadek wants to determine why only 25% of patients are “responders” to artificial hearts, meaning their cardiac muscle regenerates.
“It’s not clear why some patients respond, and some don’t, but it’s very clear that the ones who respond have the ability to regenerate heart muscle,” he said. “The exciting part now is to determine how we can make everyone a responder because if you can, you can essentially cure heart failure. The beauty of this is that a mechanical heart is not a therapy we hope to deliver to our patients in the future — these devices are tried and true, and we’ve been using them for years.”
Journal Reference:
- Wouter Derks, Julian Rode, Sofia Collin, Fabian Rost, Paula Heinke, Anjana Hariharan, Lauren Pickel, Irina Simonova, Enikő Lázár, Evan Graham, Ramadan Jashari, Michaela Andrä, Anders Jeppsson, Mehran Salehpour, Kanar Alkass, Henrik Druid, Christos P. Kyriakopoulos, Iosif Taleb, Thirupura S. Shankar, Craig H. Selzman, Hesham Sadek, Stefan Jovinge, Lutz Brusch, Jonas Frisén, Stavros Drakos, Olaf Bergmann. A Latent Cardiomyocyte Regeneration Potential in Human Heart Disease. Circulation, 2024; DOI: 10.1161/CIRCULATIONAHA.123.067156