Surgeons will soon be able to literally mend a broken heart using live tissue grown from a patient's very own stem cells, top cardiologists said.
The whole procedure -- harvesting cells from bone marrow, growing tissue and surgically implanting the heart muscle or valve -- could take as little as six weeks and could become routine within three-to-five years, they reported.
Their findings were published in a special issue of the Philosophical Transactions of The Royal Society B in Britain.
One reason heart attacks are so debilitating, even when they are not fatal, is because the human heart does not regenerate. Damaged tissue stays damaged.
Most problems occur with age, when the heart begins to wear out.
"But the highest medical need for tissue-engineered heart valves is in the treatment of congenital heart malformation," which affects nearly 1 percent of all newborns, Simon Hoeurstrup, lead author of one of the studies, said.
Artificial heart valves currently available must be periodically replaced as children grow, leading to suffering and higher death rates than in adults.
Bio-engineered heart muscle that could be grafted onto a patient's living tissue without fear of rejection by the immune system has long been a holy grail of cardiovascular medicine.
Artificial replacements "do the job and save people's lives," said heart surgeon Magdi Yacoub, who coordinated the studies. "But they cannot match the elegant, sophisticated functions of living tissues."
While durable, mechanical hardware increases the risk of bacterial infection in the heart's inner lining, as well as abnormalities in blood flow. Recipients must also take medication to prevent blood clots, boosting the chances of internal bleeding and embolisms.
There are currently two broad techniques for making bio-prosthetic heart valves, and both have serious drawbacks.
Animal grafts, especially from pigs, are readily available, but differ in structure and tend to wear out. Human valves from donors work much better, but are in chronically short supply and can easily provoke immune reactions.
In the tissue engineering approach favored by Yacoub and Hoerstrup, the patient's own stem cells -- taken from bone marrow -- are isolated and expanded in the laboratory using standard cell culture techniques.
They are then "seeded" onto a special matrix in the shape of a heart valve that is positioned in a device called a "bioreactor" which tricks the cells into growing in the right shape.
Once mature, the living-tissue heart valves can be implanted in the patient.
This procedure has already been extensively tested in sheep, but several years of follow-up are required before it can be deemed effective and safe, Hoerstrup said.
The CIA has a message for Chinese government officials worried about their place in Chinese President Xi Jinping’s (習近平) government: Come work with us. The agency released two Mandarin-language videos on social media on Thursday inviting disgruntled officials to contact the CIA. The recruitment videos posted on YouTube and X racked up more than 5 million views combined in their first day. The outreach comes as CIA Director John Ratcliffe has vowed to boost the agency’s use of intelligence from human sources and its focus on China, which has recently targeted US officials with its own espionage operations. The videos are “aimed at
STEADFAST FRIEND: The bills encourage increased Taiwan-US engagement and address China’s distortion of UN Resolution 2758 to isolate Taiwan internationally The Presidential Office yesterday thanked the US House of Representatives for unanimously passing two Taiwan-related bills highlighting its solid support for Taiwan’s democracy and global participation, and for deepening bilateral relations. One of the bills, the Taiwan Assurance Implementation Act, requires the US Department of State to periodically review its guidelines for engagement with Taiwan, and report to the US Congress on the guidelines and plans to lift self-imposed limitations on US-Taiwan engagement. The other bill is the Taiwan International Solidarity Act, which clarifies that UN Resolution 2758 does not address the issue of the representation of Taiwan or its people in
US Indo-Pacific Commander Admiral Samuel Paparo on Friday expressed concern over the rate at which China is diversifying its military exercises, the Financial Times (FT) reported on Saturday. “The rates of change on the depth and breadth of their exercises is the one non-linear effect that I’ve seen in the last year that wakes me up at night or keeps me up at night,” Paparo was quoted by FT as saying while attending the annual Sedona Forum at the McCain Institute in Arizona. Paparo also expressed concern over the speed with which China was expanding its military. While the US
SHIFT: Taiwan’s better-than-expected first-quarter GDP and signs of weakness in the US have driven global capital back to emerging markets, the central bank head said The central bank yesterday blamed market speculation for the steep rise in the local currency, and urged exporters and financial institutions to stay calm and stop panic sell-offs to avoid hurting their own profitability. The nation’s top monetary policymaker said that it would step in, if necessary, to maintain order and stability in the foreign exchange market. The remarks came as the NT dollar yesterday closed up NT$0.919 to NT$30.145 against the US dollar in Taipei trading, after rising as high as NT$29.59 in intraday trading. The local currency has surged 5.85 percent against the greenback over the past two sessions, central
RSS