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.
PREPAREDNESS: Given the difficulty of importing ammunition during wartime, the Ministry of National Defense said it would prioritize ‘coproduction’ partnerships A newly formed unit of the Marine Corps tasked with land-based security operations has recently replaced its aging, domestically produced rifles with more advanced, US-made M4A1 rifles, a source said yesterday. The unnamed source familiar with the matter said the First Security Battalion of the Marine Corps’ Air Defense and Base Guard Group has replaced its older T65K2 rifles, which have been in service since the late 1980s, with the newly received M4A1s. The source did not say exactly when the upgrade took place or how many M4A1s were issued to the battalion. The confirmation came after Chinese-language media reported
A Ministry of Foreign Affairs official yesterday said that a delegation that visited China for an APEC meeting did not receive any kind of treatment that downgraded Taiwan’s sovereignty. Department of International Organizations Director-General Jonathan Sun (孫儉元) said that he and a group of ministry officials visited Shenzhen, China, to attend the APEC Informal Senior Officials’ Meeting last month. The trip went “smoothly and safely” for all Taiwanese delegates, as the Chinese side arranged the trip in accordance with long-standing practices, Sun said at the ministry’s weekly briefing. The Taiwanese group did not encounter any political suppression, he said. Sun made the remarks when
The Taiwanese passport ranked 33rd in a global listing of passports by convenience this month, rising three places from last month’s ranking, but matching its position in January last year. The Henley Passport Index, an international ranking of passports by the number of designations its holder can travel to without a visa, showed that the Taiwan passport enables holders to travel to 139 countries and territories without a visa. Singapore’s passport was ranked the most powerful with visa-free access to 192 destinations out of 227, according to the index published on Tuesday by UK-based migration investment consultancy firm Henley and Partners. Japan’s and
BROAD AGREEMENT: The two are nearing a trade deal to reduce Taiwan’s tariff to 15% and a commitment for TSMC to build five more fabs, a ‘New York Times’ report said Taiwan and the US have reached a broad consensus on a trade deal, the Executive Yuan’s Office of Trade Negotiations said yesterday, after a report said that Washington is set to reduce Taiwan’s tariff rate to 15 percent. The New York Times on Monday reported that the two nations are nearing a trade deal to reduce Taiwan’s tariff rate to 15 percent and commit Taiwan Semiconductor Manufacturing Co (TSMC, 台積電) to building at least five more facilities in the US. “The agreement, which has been under negotiation for months, is being legally scrubbed and could be announced this month,” the paper said,
RSS