Full Coverage In-depth coverage about Heart Disease Related News Stories · Heart May Be Able To Repair Damage - Washington Post (Jun 7, 2001) · Study Finds Heart Regenerates Cells - NY Times (registration req'd) (Jun 6, 2001) · Heart May Be Able to Repair Damage - Washington Post (Jun 6, 2001) · Study: Heart Cells Could Repair Damaged Hearts - ABCNews.com (Jun 6, 2001) · Heart Shows Sign of Self-Repair After Heart Attack - Reuters (Jun 6, 2001) More... Related Web Sites · Heart and Stroke A-Z Guide - from the American Heart Association. · Heart Disease and Stroke: Ask NOAH - from the New York Online Access to Health, which seeks to provide high quality full-text health information for consumers that is accurate, timely, relevant and unbiased (in English and Spanish). · HeartPoint - created by medical professionals to provide patients with a source of credible information about heart disease. · How Cholesterol Works - provides information on different types of cholesterol and how they effect the cardiovascular system. From Howstuffworks. · How Diagnosing Heart Disease Works - learn how chest x-rays and stress tests are used in diagnosis of heart disease. Also: a look at how the heart works. From Howstuffworks.com. More... Magazine Articles · After facing the specter of an early death, reporter had a change of heart - Seattle Times (May 29, 2001) · Cholesterol Alert - Time Magazine (May 21, 2001) · Cholesterol Check - Fortune (May 17, 2001) · A heart-to-heart saves lives - Daily Telegraph (UK) (May 8, 2001) · Your heart has been recalled - Salon (Mar 2, 2001) More... Audio · Studies Link Bypass Surgery to Mental Problems - NPR (Feb 8, 2001) · 'Saving the Heart: The Battle to Conquer Coronary Disease' author Stephen Klaidman - Fresh Air with Terry Gross (Mar 7, 2000) · Binge drinking may cause heart attacks - Environmental News Network (Feb 25, 2000) More... Video · Fighting Cholesterol - Online NewsHour (May 15, 2001) · Heart Health: Defibrillators - Online NewsHour (Oct 27, 2000) · Tomatos may be key in fighting cancer and heart disease - CBC (Sep 19, 2000) News Sources · Yahoo! News Search · CNN: Health · Mayo Clinic Heart Center · Online NewsHour: Heart Health Yahoo! Categories · Heart Diseases · Heart Attack More...

Study Finds Heart Muscle Regenerates After Attack

BOSTON (Reuters) - Challenging one of medicine's long-standing beliefs, a team of scientists has found the strongest evidence to date that human heart muscle cells regenerate after a heart attack, according to a study published in Thursday's New England Journal of Medicine (news - web sites).

Scientists from New York Medical College in Valhalla, New York reported their success in finding large scale replication of heart muscle cells in two regions of the heart and in identifying several other key indicators of cell regeneration.

Dr. Piero Anversa, professor of medicine and director of the Cardiovascular Research Institute led a team that studied myocytes, or heart muscle cells, from 13 patients, 4 to 12 days after their heart attacks. The team also looked at myocytes from 10 patients who did not have cardiovascular disease.

Samples were obtained from the border zone near the site of the heart attack and from a more distant site from the damaged tissue.

By viewing these areas of the heart with a high resolution confocal microscope, Anversa and his colleagues reported they were able to measure the expression of Ki67, a protein found in the nucleus of dividing heart muscle cells. Ki67 is expressed during all phases of a cell's life cycle and is a strong indicator of cell division.

The scientists also obtained images of mitotic division and found other evidence of myocyte replication, including the formation of the ``mitotic spindle,'' and ``contractile ring,'' critical structural indicators of cell division.

Important evidence of myocardial repair was demonstrated by the mitotic index, a measurement of the degree of myocyte division. In comparison with normal hearts, the number of myocytes multiplying in diseased hearts was 70 times higher in the border zone and 24 times higher in the remote myocardium, the researchers found.

According to Anversa, the next challenge is to find the source of the dividing myocytes.

``Are these cells a sub-population of known cells that retain the capacity to divide, or are they multiplying cells that originate from stem cells present in the heart?'' he asked.

``There are preliminary indications that primitive cells like stem cells exist in the human heart. Stem cells may have the ability to develop into the various cardiac cell types and form new healthy functioning myocardium,'' he said.

``If we can prove the existence of cardiac stem cells and make these cells migrate to the region of tissue damage, we could conceivably improve the repair of damaged heart muscle and reduce heart failure.''

Research on animal models supports this possibility. In the April 4 issue of Nature, the Anversa team and a colleague at the National Institutes of Health (news - web sites) reported that adult stem cells isolated from mouse bone and injected into a damaged mouse heart became functioning heart muscle by developing into myocytes and coronary vessels.

Moreover, the newly formed tissue partially restored the heart's ability to pump blood. Although a cardiac stem cell has not yet been identified, scientists have identified a neural stem cell in the brain.

``Why not the heart?'' asked Anversa.

The heart study was funded by the National Heart, Lung and Blood Institute (NHLBI) and the National Institute on Aging.

Claude Lenfant, director of the NHLBI, a component of NIH, called it a landmark study.

``It has long been assumed that when the heart is damaged -- such as after a heart attack -- heart muscle cells do not regenerate and the damage is permanent. This assumption has been challenged in recent years by evidence that heart muscle cells may in fact regenerate.

``Now, this latest research provides the most dramatic and clear-cut demonstration to date of heart cell regeneration after cardiac injury,'' Lenfant said.

Earlier Stories
Report: Arm Cells Used in Attempt to Heal Heart (May 30)
Arm Cells Used in Attempt to Heal Heart: LA Times (May 30)

Archived Stories by Date:

Jun 06 Jun 05 Jun 04 Jun 03 Jun 02 Jun 01 May 31 May 30 May 29 May 28 May 27 May 26 May 25 May 24 May 23 May 22 May 21 May 20 May 19 May 18 May 17 May 16 May 15 May 14 May 13 May 12 May 11 May 10 May 09 May 08

News Resources Message Boards: Post/Read Msgs (2 msg Jun 7, 6:15 AM ET) Conversations: Start a live discussion News Alerts: heart disease heart cell heart muscle | New England Journal of Medicine | National Institutes of Health More Alerts: News Bulletins, News, Mobile, Stocks