Scientists develop implantable patch to repair damaged hearts

Researchers have developed an implantable patch that can repair damaged heart muscle, offering new hope for millions of people suffering from advanced heart failure. 

The breakthrough, hailed as a significant advancement in cardiovascular treatment, could provide an alternative to heart transplants and artificial heart pumps, reports The Guardian.  

Heart failure affects over 64 million people worldwide, with causes ranging from heart attacks and high blood pressure to coronary artery disease. While heart transplants remain the most effective treatment for end-stage heart failure, the severe shortage of donor organs and the high cost and complications of artificial heart pumps have made alternative solutions critical.  

Scientists believe they have found a promising approach by developing biological patches made from beating heart muscle. 

Prof Ingo Kutschka of the University Medical Center Göttingen in Germany, who co-authored the research, said, "We now have, for the first time, a laboratory-grown biological transplant available, which has the potential to stabilise and strengthen the heart muscle."  

The patches are created using cells taken from blood, which are then reprogrammed to function as stem cells. These stem cells are turned into heart muscle and connective tissue cells, embedded in a collagen gel, and cultivated in a custom-made mould. The resulting hexagonal patches are attached to a membrane, which, for human applications, measures approximately 5cm by 10cm.  

Prof Wolfram-Hubertus Zimmermann, another co-author from the University Medical Center Göttingen, highlighted the youthful nature of the muscle in the patches, saying, "We are implanting young muscle into patients with heart failure." According to the research, the muscle cells in the patches resemble those of a heart aged between four and eight years.  

Unlike direct heart muscle cell injections, which can lead to tumour formation or dangerous irregular heartbeats, the patches provide a safer alternative. They ensure higher cell retention while reducing the risk of adverse effects.  

The research, published in Nature, involved testing the patches on healthy rhesus macaques. Scientists found no evidence of tumour formation, abnormal heart rhythms, or other adverse effects. In monkeys with chronic heart failure, the patches contributed to improved heart function, including stronger contractions of the heart wall.  

The treatment has also been applied to humans. In one case, a 46-year-old woman with advanced heart failure received patches made from donor human cells, which were sutured onto her beating heart using minimally invasive surgery. Three months later, she underwent a heart transplant, allowing researchers to examine her removed heart. They found that the patches had successfully survived and developed a blood supply.  

Though donor cells require immune suppression, researchers believe using these cells rather than a patient's own would make treatment more accessible and allow for "off-the-shelf" patches with better safety testing.  

However, scientists note that the patches take three to six months to deliver therapeutic benefits, meaning they may not be suitable for all patients. So far, 15 individuals have received the patches as part of ongoing clinical trials.  

"Our ongoing clinical trial will hopefully demonstrate whether this engineered heart muscle grafts will improve cardiac function in our patients," said Kutschka.  

Zimmermann emphasised that the goal is not necessarily to replace heart transplants but to provide an option for patients with limited treatment choices.

"It is offering a novel treatment to patients that are presently under palliative care and that have a mortality of 50% within 12 months," he said.  

Experts have praised the study while acknowledging the need for further research. Prof Sian Harding of Imperial College London called it a "groundbreaking study" but pointed out that the heart muscle cells in the patch did not fully mature, and blood supply development was slow.  

Prof Ipsita Roy of the University of Sheffield also welcomed the findings, highlighting the less invasive nature of the surgery compared to heart transplants.

"It is an excellent piece of work. I'm really impressed," she said. "The concept is quite clear—you can patch up the heart wherever the heart is damaged."